oracle in hindi

Oracle in Hindi

B c c F a l n a . c o m 0 9 7 9 9 4 - 5 5 5 0 5

Kuldeep Chand This EBook starts with Professional Database Application Development Process, so that you can understand the various Theoratical Processes related to Database Designing like Requirement Identification, Database Normalization, Entity Relationship (ER) Diagram Creation, Data Flow Diagram (DFD), etc… Then I have covered SQL so that you can learn the Query Language and can Query various kinds of Data from the Database, created in First Step “Database Designing Process”. This is Standard Query Language which is approximately same in approx. all DBMS Software like Oracle, DB2, MySQL, SQL Server, etc… Then I have covered PL/SQL which is specially added Functionality in Oracle so that we can use Oracle with more control to develop Professional Database Applications. This feature is not available in any other DBMS Software. And in last part I have used Visual Basic 6 to develop Frontend of a Professioanl Database Application. So that you can understand the fundamental concepts of Professional Oracle Database Application Software Development Process properly.

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Oracle 8i/9i (SQl/PlSQl) in Hindi

■■■ Kuldeep Chand

Betalab Computer Center Falna

http://www.bccfalna.com/oracle-8i-9i-sql-plsql-in-hindi-discussion/


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Oracle 8i/9i – SQL/PLSQL in Hindi Copyright © 2009 by Kuldeep Chand All rights reserved. No part of this work may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying, recording, or by any information storage or retrieval system, without the prior written permission of the copyright owner and the publisher. Trademarked names may appear in this book. Rather than use a trademark symbol with every occurrence of a trademarked name, we use the names only in an editorial fashion and to the benefit of the trademark owner, with no intention of infringement of the trademark. Lead Editors: Kuldeep Chand Distributed to the book trade worldwide by Betalab Computer Center, Behind of Vidhya Jyoti School, Falna Station Dist. Pali (Raj.) Pin 306116 e-mail [email protected] or visit http://www.bccfalna.com For information on translations, please contact BetaLab Computer Center, Behind of Vidhya Jyoti School, Falna Station Dist. Pali (Raj.) Pin 306116 Phone 97994-55505 The information in this book is distributed on an “as is” basis, without warranty. Although every precaution has been taken in the preparation of this work, the author shall not have any liability to any person or entity with respect to any loss or damage caused or alleged to be caused directly or indirectly by the information contained in this book.



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This book is dedicated to those

who really wants to be

a

PrOfeSSiOnal develOPer



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index Of

cOntentS



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Table of Contents Database Management System ................................................................................ 16

Introduction ............................................................................................................ 16 Problem – Doing Something .................................................................................. 20 System – Interrelated Group of Units to Solve a Problem ..................................... 20 Database Management System – DBMS .............................................................. 20

Requirement of Good Database Design ............................................................ 24 Effects of Poor Database Design ....................................................................... 25 Meaningful Identifiers ......................................................................................... 30 Entities and Data Relationships ......................................................................... 31 Entities and Their Attributes ............................................................................... 31 Entity Identifiers ................................................................................................. 32 Single-Valued and Multi-Valued Attributes ........................................................ 33 Identifying Problem Related Entities .................................................................. 36 Documenting Logical Data Relationships .......................................................... 37 Entities and Attributes for Music Store Application ............................................ 38

Domains ................................................................................................................ 39 Documenting Domains ....................................................................................... 39 Practical Domain Choices .................................................................................. 39

Basic Data Relationships ....................................................................................... 42 One To One Relationships ................................................................................. 42 One To Many Relationships ............................................................................... 44 Many To Many Relationships ............................................................................. 44 Weak Entities and Mandatory Relationships ..................................................... 45 Documenting Relationships ............................................................................... 46 Dealing with Many To Many Relationships ........................................................ 49 Composite Entities ............................................................................................. 50

Relationships and Business Rules ........................................................................ 54 Data Modeling and Data Flow ............................................................................... 54 Schema ................................................................................................................. 58

Tables ................................................................................................................ 61 Views ................................................................................................................. 68 Data Dictionary .................................................................................................. 70

Normalization ......................................................................................................... 71 Translating an ER Diagram into Relations ......................................................... 71 Normal Forms .................................................................................................... 72 Equi – Join ......................................................................................................... 86

Database Structure and Performance Tuning ....................................................... 89 Indexing ............................................................................................................. 89 Clustering ........................................................................................................... 91 Partitioning ......................................................................................................... 92

Oracle – The History ................................................................................................. 95 The Relational Database Architecture ................................................................... 95

File-Based Systems ........................................................................................... 96 Client/Server Architecture .................................................................................. 97 Multi-Tire Architecture ........................................................................................ 98

Network Computing Architecture ........................................................................... 99 Clients ................................................................................................................ 99 Application Server .............................................................................................. 99 Universal Data Server ........................................................................................ 99

Oracle - Architecture ............................................................................................... 101



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Memory Structures .............................................................................................. 101 The Database Buffer Cache ............................................................................ 102 Redo Log Buffer ............................................................................................... 103 Shared Pool ..................................................................................................... 103 Additional Memory Areas ................................................................................. 104

Processes ............................................................................................................ 104 Database Writer (DBWR) ................................................................................. 106 Log Writer (LGWR) .......................................................................................... 107 System Monitor (SMON) .................................................................................. 107 Process Monitor (PMON) ................................................................................. 108 Archiever (ARCH) ............................................................................................ 108 Server Processes ............................................................................................. 108 Listener Process .............................................................................................. 109

Database Files ..................................................................................................... 109 Control Files ..................................................................................................... 109 Parameter Files ................................................................................................ 110 Online Redo Log Files ..................................................................................... 113 Data Files ......................................................................................................... 114

Data Concurrency and Data Consistency ............................................................... 118 Data Concurrency ................................................................................................ 118 Data Consistency ................................................................................................ 118

Locking Strategies ........................................................................................... 118 Consistency Achievement ................................................................................ 119 Schemas .......................................................................................................... 119

Creating a Database ............................................................................................... 124 Administration Tools ............................................................................................ 124

Identifying Database ........................................................................................ 124 SQL *Plus ........................................................................................................ 124 Server Manager ............................................................................................... 125 NT Instance Manager ...................................................................................... 125

Oracle 8i Installation ............................................................................................ 125 Configuring The Network ..................................................................................... 142

Tnsnames.ora .................................................................................................. 151 Listener.ora ...................................................................................................... 153

Application Development Process .......................................................................... 156 Finding The Requirements Of The Application .................................................... 156 Designing The Database ..................................................................................... 157 Designing The Application ................................................................................... 158 Enforcing Security ............................................................................................... 158 Performance Tuning ............................................................................................ 159 Maintaining and Updating .................................................................................... 159

Database Design ..................................................................................................... 161 Conceptual Design .............................................................................................. 162

Entity-Relationship Diagrams ........................................................................... 163 Logical Design ..................................................................................................... 166

Identifying the Record Types and Fields .......................................................... 167 Identifying Any Data Dependencies ................................................................. 167 Normalizing The Database .............................................................................. 168 Database De-Normalization ............................................................................. 175 Keys ................................................................................................................. 175

Database Design – An Example from Start To End ................................................ 180 Entity Relationship Modeling ............................................................................... 180



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Step 1 – Finding Database Application Related Entities .................................. 180 Step 2 – Determining Relationship between Entity Pairs ................................. 181 Step 3 – Determining Relationship Nature ....................................................... 181 Step 4 – Resolving Many To Many Relationship ............................................. 182 Step 5 – Foreign Keys For Enforcing Relationships ........................................ 183 Step 6 – Entity Attributes Setup ....................................................................... 183

Database Normalization ...................................................................................... 184 First Normal Form ( FNF or 1NF ) .................................................................... 185 Second Normal Form ( SNF or 2FN) ............................................................... 188 Third Normal Form (TNF or 3NF) .................................................................... 189

Database Implementation ....................................................................................... 193 Tablespace Creation ........................................................................................... 193

Creating Tablespace ........................................................................................ 194 Optional Parameters ........................................................................................ 196

Table Creation ..................................................................................................... 199 Oracle Data Types ........................................................................................... 199 Creating Tables ................................................................................................ 202 USER_CONSTRAINTS Table ......................................................................... 235 Table Modification ............................................................................................ 237 Data Dictionary ................................................................................................ 241

Index Creation ..................................................................................................... 242 Creating Index .................................................................................................. 245

Sequences Creation ............................................................................................ 246 Creating Sequence .......................................................................................... 247 Maintaining Sequence ..................................................................................... 251

Audit Trails ........................................................................................................... 254 Other Schema Objects ........................................................................................ 255

Clusters ............................................................................................................ 256 Views ............................................................................................................... 258 Synonyms ........................................................................................................ 266

User Access Controlling ...................................................................................... 266 Privileges ......................................................................................................... 267 Schemas .......................................................................................................... 267 System Privileges ............................................................................................ 267 Role .................................................................................................................. 269 Object Privileges .............................................................................................. 270

Accessing Data – SQL Queries .............................................................................. 277 SQL Overview ..................................................................................................... 277 Types Of SQL Commands .................................................................................. 277

Query Commands ............................................................................................ 278 Data Definition Language (DDL) Commands .................................................. 278 Data Control Language (DCL) Commands ...................................................... 278 Data Manipulation Language (DML) Commands ............................................. 278 Transaction Control Language (TCL) Commands ........................................... 278 Session Control Commands ............................................................................ 278 System Control Commands ............................................................................. 278 Embedded SQL Commands ............................................................................ 278

SELECT Command ............................................................................................. 279 SELECT Syntax ............................................................................................... 279 Using Dual ....................................................................................................... 281 Getting Selected Rows .................................................................................... 281 Sorting The Selection ....................................................................................... 282



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Useful Operators ................................................................................................. 283 = Equality Test ............................................................................................. 283 != Inequality Test (Not Equal To) .................................................................. 283 > Greater Than ............................................................................................ 283 < Less Than ................................................................................................. 283 >= Greater Than OR Equal To .............................................................. 284 <= Less Than OR Equal To ................................................................... 284 | | Character String Concatenation................................................................ 284 AND Returns TRUE If Both Conditions Are TRUE Otherwise FALSE ..... 284 OR Returns TRUE If Either Conditions Is TRUE Otherwise FALSE ...... 285 NOT Returns TRUE If Condition Is False and Vise Versa ........................ 285 BETWEEN a AND b ......................................................................................... 285 IN ..................................................................................................................... 285 IS NULL ........................................................................................................... 286 LIKE ................................................................................................................. 286

Calculated Fields ................................................................................................. 286 Oracle-Specific Functions .................................................................................... 287

SYSDATE ........................................................................................................ 287 USER ............................................................................................................... 287 TO_CHAR() ..................................................................................................... 287 TO_DATE() ...................................................................................................... 288 CONCATE() ..................................................................................................... 288 UPPER() .......................................................................................................... 288 LOWER() ......................................................................................................... 288 INITCAP() ........................................................................................................ 288 DECODE Function ........................................................................................... 289

GROUP Function ................................................................................................. 291 AVG (Column_Name) ...................................................................................... 292 COUNT (Column_Name) ................................................................................. 292 MAX (Column_Name) ...................................................................................... 292 MIN (Column_Name) ....................................................................................... 292 STDDEV(Column_Name) ................................................................................ 292 SUM(Column_Name) ....................................................................................... 292 VARIANCE(Column_Name) ............................................................................ 292

GROUP BY Clause ............................................................................................. 293 HAVING Clause ................................................................................................... 294 Join - Query with More Than One Table.............................................................. 294

Outer Join ........................................................................................................ 296 Subqueries .......................................................................................................... 296

Subqueries That Return Only One Value ........................................................ 297 Subqueries That Return More Than One Row................................................. 297

Database Optimizer ............................................................................................. 298 Efficient SELECT Statements .............................................................................. 299 Specifying Schemas ............................................................................................ 300

Updating Database ................................................................................................. 304 Tables Updating Philosophy ................................................................................ 304

INSERTING Rows ........................................................................................... 304 UPDATING Rows ............................................................................................ 307 DELETING Rows ............................................................................................. 308

Transaction Control ............................................................................................. 310 COMMIT .......................................................................................................... 311 ROLLBACK ...................................................................................................... 311



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SAVEPOINT name .......................................................................................... 311 ROLLBACK TO SAVEPOINT name ................................................................ 311

Database Triggers ............................................................................................... 313 CREATE TABLE AS Subquery ........................................................................... 314 Database Design For Fast Updates .................................................................... 315 Date Data Type ................................................................................................... 315

Complete SQL – Structured Query Language ........................................................ 319 iSQL *Plus Terminal ............................................................................................ 319 Making Simple Queries ....................................................................................... 320 Making Conditional Queries ................................................................................ 326 Making Sorted Queries ........................................................................................ 331 Character Functions ............................................................................................ 334

CONCAT Function ........................................................................................... 334 INITCAP Function ............................................................................................ 336 LOWER and UPPER Function ......................................................................... 336 LPAD and RPAD Function ............................................................................... 336 SUBSTR Function ............................................................................................ 337 LTRIM and RTRIM Functions .......................................................................... 338 INSTR Functions .............................................................................................. 339 LENGTH Functions .......................................................................................... 340

Numerical Functions ............................................................................................ 340 MOD Functions ................................................................................................ 341 POWER Functions ........................................................................................... 341 ROUND Functions ........................................................................................... 341 SIGN Functions ................................................................................................ 342 SQRT Functions .............................................................................................. 342 TRUNC Functions ............................................................................................ 343

Date Functions .................................................................................................... 343 ADD_MONTHS Functions ............................................................................... 343 LAST_DAY Functions ...................................................................................... 344 MONTHS_BETWEEN Functions ..................................................................... 344 NEXT_DAY Functions ..................................................................................... 344

Making Aggregate Queries .................................................................................. 345 Making Join Queries ............................................................................................ 348

Cartesian Products .......................................................................................... 351 Equi - Join ........................................................................................................ 352 Non-Equi-Join .................................................................................................. 354 Outer Join ........................................................................................................ 354 Self Join ........................................................................................................... 356 Creating Cross Joins ........................................................................................ 356 Creating Natural Joins ..................................................................................... 357 Left Outer Join ................................................................................................. 359 Right Outer Join ............................................................................................... 360 Full Outer Join .................................................................................................. 361

Making Subqueries .............................................................................................. 361 Making DML Queries ........................................................................................... 369

State of the Data Before COMMIT and ROLLBACK ........................................ 374 State of the Data after COMMIT ...................................................................... 374 State of the Data after ROLLBACK .................................................................. 375

Introduction to PL/SQL ............................................................................................ 378 PL/SQL – The Extension of SQL ......................................................................... 378

Advantages Of PL/SQL .................................................................................... 379



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PL/SQL Execution Environment ...................................................................... 379 Stored Procedures ............................................................................................... 380

Stored Procedures – The Advantages ............................................................. 380 Procedure Structure ......................................................................................... 382 Function Structure ............................................................................................ 383 Trigger Structure .............................................................................................. 384 Procedure Parameters ..................................................................................... 384

Packages ............................................................................................................. 385 Package Creation ............................................................................................ 386 Built-In Packages ............................................................................................. 386

Stored Procedures Creating Tools ...................................................................... 388 SQL *Plus ........................................................................................................ 388 Visual Database Tools ..................................................................................... 390 Oracle Procedure Builder ................................................................................. 393 Error Handling in PL/SQL ................................................................................ 404 Enhancing The Error Message ........................................................................ 407

Creating Stored Procedures .................................................................................... 410 PL/SQL Data Types ............................................................................................. 410

Scalar Data Types ........................................................................................... 410 User-Defined (Composite) Variables ............................................................... 412

Declaring Variables ............................................................................................. 412 %TYPE and %ROWTYPE ............................................................................... 413

Declaring Constants ............................................................................................ 414 Statements and Assignments .............................................................................. 414 Flow Control Statements ..................................................................................... 415

Decision Flow Control ...................................................................................... 415 Loops ............................................................................................................... 416

Using SQL Statements In PL/SQL ...................................................................... 418 Update Statements .......................................................................................... 418 Using SELECT INTO ....................................................................................... 419 Exceptions In SELECT INTO Statement ......................................................... 422

PL/SQL Cursors .................................................................................................. 423 Declaring A PL/SQL Cursor ............................................................................. 424 Opening And Closing A PL/SQL Cursor .......................................................... 424 Fetching A PL/SQL Cursor .............................................................................. 425 Error Conditions for PL/SQL Cursors ............................................................... 425 PL/SQL Cursor In Action .................................................................................. 426 PL/SQL Cursor Loops ...................................................................................... 428

User-Defined Data Types .................................................................................... 429 Records ............................................................................................................ 429 PL/SQL Tables and Collections ....................................................................... 430

Cursor Variables .................................................................................................. 435 Declaring a Cursor Variable ............................................................................. 436 Opening A Cursor Variable .............................................................................. 436 Fetching Records ............................................................................................. 437 Closing The Cursor Variable ............................................................................ 437 Passing Cursor Variables ................................................................................ 438

Using Triggers ..................................................................................................... 439 Providing a Transaction Audit .............................................................................. 441 Procedures and Visual Basic ............................................................................... 443

Data Controls ................................................................................................... 443 Data Access Objects (DAO) ............................................................................ 443



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Remote Data Objects (RDO) ........................................................................... 444 ActiveX Data Objects (ADO) ............................................................................ 444 Oracle Objects or OLE (OO4O) ....................................................................... 444

Distributed Databases ............................................................................................. 446 Overview .............................................................................................................. 446 Centralized and Client-Server Architecture ......................................................... 446 Parallel Systems .................................................................................................. 447 Distributed Systems ............................................................................................. 447

Client-Side Technology ........................................................................................... 449 The Software Layers ........................................................................................... 449

The ODBC Driver Manager .............................................................................. 449 ODBC Driver .................................................................................................... 449 The OLE-DB Layer .......................................................................................... 450 Oracle Call Interface ........................................................................................ 450 Net8 and SQL *Net .......................................................................................... 451 The Network Softwares .................................................................................... 451

ODBC .................................................................................................................. 452 The Origins Of ODBC ...................................................................................... 452 ODBC Drivers .................................................................................................. 452 Selecting An ODBC Driver ............................................................................... 454 Setting Up An ODBC Data Source .................................................................. 454 Creating An ODBC Connection String ............................................................. 457 Testing Of ODBC Connection .......................................................................... 458

OLE-DB ............................................................................................................... 460 Data Providers ................................................................................................. 461 Data Consumers .............................................................................................. 461 OLE-DB Cursors .............................................................................................. 462 How Cursor Works? ......................................................................................... 465 Choosing A Cursor ........................................................................................... 465

Connections ......................................................................................................... 466 DSN-Less Connections .................................................................................... 467 Closing An ODBC Connection ......................................................................... 467 ODBC Connection Pooling .............................................................................. 468 Pre-Started Connections .................................................................................. 468

Alternative Access Methods ................................................................................ 469 Oracle Pre-Compilers ...................................................................................... 469 Oracle Objects for OLE .................................................................................... 469

Accessing Oracle from Visual Basic ....................................................................... 471 The JET Engine ............................................................................................... 471 Data Access Objects ........................................................................................ 476 Data Control ..................................................................................................... 477 Remote Data Objects ....................................................................................... 478 ODBCDirect ..................................................................................................... 479 The ODBC API ................................................................................................. 481 ActiveX Data Objects ....................................................................................... 481 Oracle Objects for OLE .................................................................................... 483

Oracle Objects for OLE ........................................................................................... 487 The OO4O Object Hierarchy ............................................................................... 487

OraClient .......................................................................................................... 487 OraSession ...................................................................................................... 488 OraConnection ................................................................................................. 488 OraDatabase .................................................................................................... 488



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The Early Binding Issue ....................................................................................... 488 Accessing Database ............................................................................................ 490

BeginTrans ....................................................................................................... 490 CommitTrans ................................................................................................... 490 ConnectSession ............................................................................................... 490 CreateNamedSession ...................................................................................... 490 LastServerErrResetSession ............................................................................. 491 OpenDatabase ................................................................................................. 491 ResetTrans ...................................................................................................... 491 Rollback ........................................................................................................... 491

Connection With Database .................................................................................. 491 Database_Name .............................................................................................. 491 Connect_String ................................................................................................ 491 Options ............................................................................................................. 491

Database Object Methods ................................................................................... 493 Close ................................................................................................................ 493 CreateCustomDynaset ..................................................................................... 493 CreateDynaset ................................................................................................. 494 CreatePLSQLDynaset ..................................................................................... 494 CreatePlsqlCustomDynaset ............................................................................. 494 CreateSQL ....................................................................................................... 494 ExecuteSQL ..................................................................................................... 494 LastServerErrReset ......................................................................................... 494

Creating OraDynasets ......................................................................................... 494 Source .............................................................................................................. 495 Options ............................................................................................................. 495 Pessimistic Locking .......................................................................................... 496

Using Triggers ..................................................................................................... 498 Tuning The OraDynaset ...................................................................................... 499

Cache Parameters ........................................................................................... 499 Fetch Parameters ............................................................................................ 500

OraDynaset Properties ........................................................................................ 500 BOF .................................................................................................................. 500 Bookmark ......................................................................................................... 500 BookMarkable .................................................................................................. 501 CacheBlocks .................................................................................................... 501 CacheChanged ................................................................................................ 501 CacheSliceSize ................................................................................................ 501 CacheSizePerBlock ......................................................................................... 501 Connection ....................................................................................................... 501 Database .......................................................................................................... 501 EditMode .......................................................................................................... 501 EOF .................................................................................................................. 501 FetchLimit ........................................................................................................ 501 FetchSize ......................................................................................................... 501 Fields ............................................................................................................... 502 LastModified ..................................................................................................... 502 NoMatch ........................................................................................................... 502 Options ............................................................................................................. 502 RecordCount .................................................................................................... 502 RowPosition ..................................................................................................... 502 Session ............................................................................................................ 502



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SQL .................................................................................................................. 502 Transactions .................................................................................................... 502 Updatable ......................................................................................................... 502

Exploring The OraDynaset Methods ................................................................... 503 Populating OraDynaset .................................................................................... 503 Changing The Current Record ......................................................................... 504 Accessing The Fields Of An OraDynaset ........................................................ 505 Changing the Records and Values in an OraDynaset ..................................... 506 Finding A Particular Record ............................................................................. 508 Closing A Dynaset ........................................................................................... 509

Using Parameters ................................................................................................ 509 Name ............................................................................................................... 510 InitialValue ....................................................................................................... 510 Type ................................................................................................................. 510

Executing SQL Commands ................................................................................. 512 Calling Stored Procedures ................................................................................... 513 Retrieving Cursor Variables ................................................................................. 514

SQLStatement ................................................................................................. 514 CursorName ..................................................................................................... 515 Options ............................................................................................................. 515

Calling PL/SQL Functions ................................................................................... 516 Retrieving PL/SQL Tables ................................................................................... 517

Name ............................................................................................................... 517 Type ................................................................................................................. 517 ServerType ...................................................................................................... 517 ArraySize ......................................................................................................... 518 ElementSize ..................................................................................................... 518

Using OraSQLStmts ............................................................................................ 519 Sql_Statement ................................................................................................. 519 Options ............................................................................................................. 519

Batch Updates ..................................................................................................... 520 Error Handling ..................................................................................................... 522 Putting It All Together .......................................................................................... 522 Viewing The Structure Of A Database ................................................................. 524

OralDataType ................................................................................................... 524 OraMaxDSize ................................................................................................... 524 OraMaxSize ..................................................................................................... 525 OraNullOK ........................................................................................................ 525 OraPrecision .................................................................................................... 525 OraScale .......................................................................................................... 525 Size .................................................................................................................. 525 Truncated ......................................................................................................... 525 Type ................................................................................................................. 525 Value ................................................................................................................ 525

ActiveX Data Objects (ADO) ................................................................................... 528 ADO Object Model ............................................................................................... 528

Connection Object ........................................................................................... 529 Recordset Object ............................................................................................. 529 Command Object ............................................................................................. 530 Parameter Object ............................................................................................. 530 Field Object ...................................................................................................... 530 Error Object ...................................................................................................... 530



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Property Object ................................................................................................ 530 Connecting To Oracle .......................................................................................... 531

Connection Object Methods ............................................................................. 531 Connection Object Properties .......................................................................... 533 Opening Connection ........................................................................................ 535 2-Ways For Opening Connection ..................................................................... 535 ADO Events ..................................................................................................... 538 WithEvents ....................................................................................................... 539

Working With Recordset ...................................................................................... 541 Opening Recordset .......................................................................................... 541 Populating The Recordset ............................................................................... 544 Fetching Multiple Rows .................................................................................... 545 ADO Recordset Navigation .............................................................................. 546 Changing The Rows and Values In A Recordset ............................................. 547 Searching A Record In Recordset ................................................................... 548 Closing A Recordset ........................................................................................ 548 Recordset Events ............................................................................................. 548

The Command Object ......................................................................................... 550 Command Properties ....................................................................................... 550 Command Parameters ..................................................................................... 552 Command Object Properties ............................................................................ 554 Executing SQL Commands .............................................................................. 557

Stored Procedures ............................................................................................... 558 Calling Stored Procedures ............................................................................... 559

Last but not Least. There is more… ........................................................................ 560



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dBMS dataBaSe

ManageMeMnt SySteM



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Introduction lH;rk dh “kq:vkr ls gh ekuo dks Information dh t:jr jgh gSA blhfy, og le;≤ ij lwpukvksa dks ,df=r djus o mu lwpukvksa ds vk/kkj ij lgh o mfpr fu.kZ; ysus ds u, o fodflr rjhds [kkstrk jgk gSA lwpuk dh vko”;drk o egRo ds dkj.k lcls igyk vkfo’dkj dkxt o dye dk gqvkA tSls&tSls ekuo dk fodkl gksrk x;k oSls&oSls mlus u, “kgj] jkT; o ns”k cuk, vkSj mu ns”kksa ds chp O;kikj o okf.kT; ds dkj.k fofHkUu lEca/k cus vkSj vkt dsoy O;kikj o okf.kT; gh ugha cfYd thou dh yxHkx gj lwpuk dk Internet ds ek/;e ls bu ns”kksa ds chp vknku iznku gks jgk gSA d`f’k Øakfr o vkS/kksfxd Øakfr ds ckn vkt ge lwpuk Øakfr ds ;qx esa th jgs gSaA igys lwpukvksa dks feV~Vh ds crZuksa ij fp=kRed :i esa o “kCnksa ds :i esa fy[kk tkrk FkkA fQj dkxt o dye ds fodkl ls bu ij fofHkUu lwpukvksa dks Store djds j[kk tkus yxk vkSj vkt ge bUgha lwpukvksa dks Computer ij Manage djrs gSaA fofHkUu izdkj ds vkadMksa (Data) dk ladyu (Collection) djuk vkSj fQj mu vkadMksa dks fofHkUu izdkj ls oxhZd`r (Classify) djds mudk fo”ys’k.k (Analyze ) djuk rFkk mfpr le; ij mfpr fu.kZ; ysus dh {kerk izkIr djuk] bl iwjh izfØ;k dks Computer dh Hkk’kk esa Data Processing djuk dgk tkrk gSA vkt ge ns[k ldrs gSa fd Computer dk mi;ksx fofHkUu izdkj ds Business ls lEcaf/kr lwpukvksa dks Store, Manage o Process djus ds fy, fd;k tkrk gSA Business Hkys NksVk gks ;k cMk] Computer dh viuh dqN fo”ks’krkvksa ds dkj.k lHkh izdkj ds Businesses esa bUlkuksa ds lkFk&lkFk vc Computer dk vf/kdkf/kd iz;ksx fd;k tkus yxk gSA tc ge Computer ij fdlh leL;k dk lek/kku izkIr djuk pkgrs gSa] rc ml leL;k dks gesa Computer esa ,d Software Application ds :i esa Represent djuk gksrk gSA Computer



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gesa”kk fdlh uk fdlh Software Application ds vk/kkj ij gh dke djrk gS vkSj ;fn fdlh leL;k dk lek/kku izkIr djus ds fy, Develop fd;k x;k Software Application iwjh rjg ls lgh gks] rks Computer dHkh Hkh xyr Result iznku ugha djrk gSA ;gh Computer dh lcls igyh o lcls cMh fo”ks’krk gS] fd og gesa”kk Software Application ds vk/kkj ij gh dke djrk gS] blfy, mlls izkIr gksus okyk Result dHkh Hkh xyr ugha gksrkA ;kuh Computer gesa”kk Accurate Result Provide djrk gSA ysfdu ;fn leL;k dk lek/kku izkIr djus ds fy, Develop fd, x, Software Application ds Design esa dksbZ xMcM gks] rks Computer Lo;a ml xyrh dks idM dj lgh fu.kZ; ysus esa l{ke ugha gksrk gSA bl fLFkfr esa Computer xyr Result Hkh ns ldrk gS] ftlds ckjs esa gesa”kk Software Application Develop djus okys Programmer dks lko/kku jguk gksrk gSA Computer dh nwljh fo”ks’krk ;s gS fd Computer Calculations ls lEcaf/kr dke cgqr gh lQyrkiwoZd o rsth ls dj ldrk gS] ftUgsa djus esa bUlkuksa dks dkQh le; yxrk gS vkSj fo”ks’k lko/kkuh cjruh iMrh gSA Computer Calculation ls lEcaf/kr xyfr;ka dHkh Hkh ugha djrk gS] tc rd fd Computer ftl Software Application ds vk/kkj ij Calculation dj jgk gS] ml Application dks gh xyr rjg dh Calculations dks Perform djus ds fy, Design uk fd;k x;k gksA pwafd Computer Calculations dks Fastly o Accurately Perform djrk gS] blfy, Computer ds dkj.k Business Man dks Calculation ds izfr fo”ks’k lko/kku jgus dh t:jr ugha jg tkrh gSA bl fLFkfr esa ,d Business Man vius O;kikj dks c<kus ls lEcaf/kr fu.kZ;ksa dks tYnh ls o vklkuh ls ys ldus esa l{ke gks tkrk gSA Computer dh ,d rhljh fo”ks’krk ;s gS fd vke bUlkuksa dh rjg gh Computer Hkh lwpukvksa dks ;kn j[k ldrk gSA ysfdu pwafd bUlkuksa dh ,d deh ;s Hkh gS fd os ;fn fdlh Information dks yEcs le; rd mi;ksx esa uk ysa] rks os ckrksa dks Hkwy tkrs gSa] tcfd Computer ij Stored lwpukvksa dks Computer dHkh Hkh ugha Hkwyrk gSA Computer ij Stored lwpukvksa dks ,d Business Man lkyksa ckn Hkh T;ksa dk R;ksa izkIr dj ldrk gS] ftlls ,d Business Man dks bUlkuh xyfr;ksa ls gksus okyh ijs”kkfu;ksa dk Hkh lkeuk ugha djuk iMrk gSA ,slh gh vkSj Hkh cgqr lh fo”ks’krkvksa ds dkj.k gh vkt gj Business Man pkgs og NksVk Business dj jgk gks ;k cMk] Computer ij gh vius Business ls lEcaf/kr lwpukvksa dks Manage djrk gSA gj Business Man Computer ij vius Business ls lEcaf/kr t:jh Data dks Maintain djrk gS] rkfd og vius Business ls lEcaf/kr tkudkfj;ksa dks vPNh rjg ls o rsth ls izkIr dj lds o vius Business ls lEcaf/kr fu.kZ; ys ldsA Data – Value or a Set of Values vfl) rF; (Facts) vad (Figures) o lkaf[;dh (Statics) dk og lewg ftl ij izfØ;k (Processing) djus ij ,d vFkZiw.kZ (Meaningful) lwpuk (Information) izkIr (Generate) gks] Data dgykrk gSA Data eku ;k ekuksa dk ,d lewg (Value or a Set of Values) gksrk gS] ftlds vk/kkj ij (After Processing) ge fu.kZ; (Decision) ysrs gSaA



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bls ,d mnkgj.k }kjk le>us dh dksf”k”k djrs gSaA la[;k,a (0 ls 9 rd) dqy nl gh gksrh gSaA ysfdu ;fn bUgsa ,d O;ofLFkr Øe esa j[k fn;k tk,] rks ,d lwpuk Generate gksrh gSA blfy, ;s la[;k,a Data gSaA vaxzsth Hkk’kk esa Small o Capital Letters ds dqy 52 Characters gh gksrs gSa] ysfdu ;fn bUgsa ,d lqO;ofLFkr Øe esa j[kk tk,] rks gtkjksa iqLrdsa cu ldrh gSaA blfy, ;s Characters Data gSaA Computer esa ge bUgha nks :iksa esa okLrfod thou dh fofHkUu ckrksa dks Store djrs gSa vkSj mu ij Processing djds vko”;drkuqlkj Information Generate djrs gSaA tSls fdlh School ds fofHkUu Students dh ;s tkudkjh j[kuh gks fd fdlh Class esa dkSu&dkSu ls Students gSa] mudk Serial Number D;k gS vkSj os fdl Address ij jgrs gSa] rks ;s lHkh rF; vfl) :i esa Computer ds fy, Data gSa D;ksafd fdlh Student ds Serial Number dks 0 ls 9 ds dqN vadksa ds lewg ds :i esa Express fd;k tkrk gS vkSj Student dk uke o irk Characters ds ,d lqO;ofLFkr lewg ds :i esa Express fd;k tkrk gSA tc 0 ls 9 rd ds dqN vadksa dks ,d lewg esa O;ofLFkr fd;k tkrk gS rc fdlh ,d Student dk ,d Serial Number cu tkrk gS vkSj tc fofHkUu Characters dks ,d lewg esa O;ofLFkr fd;k tkrk gS] rc fdlh Student dk uke o Address cu tkrk gSA ;s uke o Address gh fdlh Student dh dqN Information iznku djrs gSaA Processing – Generating Results Data tSls fd v{kj] vad] lka[;dh Statics ;k fdlh fp= dks lqO;ofLFkr djuk ;k mudh Calculation djuk] Processing dgykrk gSA fdlh Hkh Processing es fuEUk dke gksrs gSa% Calculation fdlh eku dks tksMuk] ?kVkuk] xq.kk djuk] Hkkx nsuk vkfnA Comparison dksbZ eku cMk] NksVk] “kwU;] Positive, Negative, cjkcj gS vkfnA Decision Masking fdlh Condition ds vk/kkj ij fu.kZ; ysukA Logic vko”;d ifj.kke dks izkIr djus ds fy, viuk;k tkus okyk Steps

dk ØeA dsoy vadksa dh x.kuk djuk gh Processing ugha dgykrk gSA cfYd fdlh Hkh izdkj ds eku dks tSls fd fdlh Document esa ls xyfr;ksa dks [kkstus dh izfØ;k ;k dqN ukeksa ds lewg dks vkjksgh (Ascending) ;k vojksgh (Descending) Øe esa O;ofLFkr djus dh izfØ;k dks Hkh Processing gh dgrs gSaA Computer esa Keyboard ls tks Hkh Data Input fd;k tkrk gS] ml Data dk rc rd dksbZ vFkZ ugha gksrk gS] tc rd fd Computer }kjk ml Data ij fdlh izdkj dh dksbZ Processing uk dh tk,A tSls mnkgj.k ds fy, Computer esa R, a, d, h, a ;s ikap v{kj vyx&vyx Input fd, tkrs gSaA blfy, ;s lHkh v{kj Row Data ds leku gSaA Computer bu ikapksa v{kjksa ij Processing djds bUgsa ,d Øe esa O;ofLFkr dj nsrk gS vkSj gesa “Radha” uke iznku djrk gS tks fd ,d vFkZiw.kZ lwpuk (Information) gSA Information – Processed Data



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ftl Data ij Processing gks pqdh gksrh gS] mls Processed Data ;k Information dgrs gSaA nwljs “kCnksa esa dgsa rks fdlh Data ij Processing gksus ds ckn tks vFkZiw.kZ ifj.kke (Result) izkIr gksrk gS] mls gh lwpuk (Information) dgrs gSaA ,d Processing ls Generate gksus okyh fdlh Information dks ge fdlh nwljh Processing esa fQj ls Data ds :i esa mi;ksx esa ysdj ubZ Information Generate dj ldrs gSa vkSj ;s Øe vkxs Hkh tkjh j[kk tk ldrk gSA mnkgj.k ds fy, R, a, m, K, i, l, l, e, d, R, a, v, a, n ;s Characters ge vyx&vyx Input djrs gSaA Computer igys bu ij Processing djds Ram, Killed, o Ravan rhu “kCn cukrk gS] tks fd gekjs fy, rhu vyx lwpukvksa dks Represent djrk gSA D;ksafd Ram. Ravan o Killed rhuksa gh “kCn vius vki esa ifjiw.kZ gSa] blfy, ;s rhuksa gh “kCn ,d izdkj dh lwpuk gSa tcfd ;fn “Ram Killed Ravan” fy[kk tk, rks bl okD; ds fy, ;s rhuksa gh “kCn ,d Data ds leku gSa] tks Processing ds dkj.k vkil esa ,d O;ofLFkr Øe esa Arrange gksdj ,d lwpuk iznku djrs gSaA lkjka”k esa dgsa rks Computer esa ge lHkh izdkj dh lwpukvksa dks Data ds vk/kkj ij Store djrs gSaA bu Data ij Processing djrs gSa] ftlls lwpuk,a Generate gksrh gSa vkSj bu lwpukvksa ds vk/kkj ij ge fu.kZ; ysrs gSaA Data okLro esa dksbZ vad] v{kj ;k fp= gks ldrk gSA Computer esa bUgha vadksa] v{kjksa ;k fp=ksa dks ekuksa ds :i esa Manage fd;k tkrk gSA ;kuh Computer ds lUnHkZ esa Data okLro esa dksbZ eku ;k ekuksa dk ,d lewg gksrk gSA What is a Computer Computer ,d ,slhElectronic Machine gS] tks funsZ”kksa ds lewg ¼ftls Program dgrs gSa½ ds fu;a=.k esa Data ;k rF;ksa ij Processing djds Information Generate djrk gSA Computer esa Data dks Accept djus vkSj ml Data ij Required Processing djus ds fy, fdlh Program dks Execute djus dh {kerk gksrh gSA ;s fdlh Data ij Mathematical o Logical fØ;k,a djus esa l{ke gksrk gSA Computer esa Data dks Accept djus ds fy, Input Devices gksrh gS] tcfd Processed Data ;kuh Information dks izLrqr djus ds fy, Output Devices gksrh gSaA Data ij Processing dk dke ftl Device }kjk lEiUu gksrk gS] mls Central Processing Unit ;k CPU dgrs gSaaA ;s ,d Microprocessor gksrk gS] ftls Computer dk fnekx Hkh dgrs gSaaA fdlh Hkh Computer fuEufyf[kr {kerk,a gksrh gSa%

1 User }kjk Supplied Data dks Accept dj ldrk gSA

2 Input fd, x, Data dks Computer dh Memory esa Store djds Required ifj.kke izkIr djus ds fy, fdlh Instructions ds lewg ;kuh fdlh Program dks Execute dj ldrk gS] tks fd ml Input fd, x, Data ij Processing dj ldrk gSA

3 Data ij Mathematical o Logical fØ;kvksa (Operations) dks fØ;kfUor (Perform) dj ldrk gSA

4 User dh vko”;drkuqlkj Output iznku dj ldrk gSA



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Problem – Doing Something Computer }kjk ge fdlh uk fdlh izdkj dh leL;k dk lek/kku izkIr djus ds fy, gh fofHkUu izdkj ds Programs fy[krs gSaA blfy, lcls igys gesa ;gh r; djuk gksxk fd vkf[kj ge Computer ds lanHkZ esa fdl ckr dks ,d leL;k ds :i esa ns[k ldrs gSa \ ;fn fcYdqy gh ljy “kCnksa esa fdlh leL;k dks ifjHkkf’kr djsa] rks Computer ij ge ftl fdlh Hkh dke dks Perform djds fdlh izdkj dk dksbZ Result izkIr djuk pkgrs gSa] ge ml dke dks leL;k ds :i esa ns[k ldrs gSaA mnkgj.k ds fy, nks la[;kvksa dk ;ksx djuk] fdlh ifj.kke dks Computer ds Monitor ij Display djuk] fdlh Hkh izdkj dh dksbZ Calculation ;k Comparison djuk vkfn bu lHkh dkeksa dks ge leL;k ds :i esa ns[k ldrs gSaA ;kuh ge tks dqN Hkh djuk pkgrs gSa] og lcdqN Computer ds fy, ,d leL;k gh gSA

System – Interrelated Group of Units to Solve a Problem Computer ,d System gksrk gSA tc fdlh ,d ;k ,d ls vf/kd leL;kvksa dks lqy>kus ;k fdlh y{; dks izkIr djus ds fy, dbZ Lora= bdkbZ;ka (Individual Units) feydj dke dj jgs gksrs gSa] rks mu bdkbZ;ksa ds lewg dks System dgk tkrk gSA tSls dksbZ Hospital ,d System gksrk gS ftls Hospital System dgk tkrk gSA Doctors, Nurses, fpfdRlk ls lEcaf/kr fofHkUu midj.k] Operation Theater, Patient vkfn fdlh Hospital System dh fofHkUu bdkbZ;ka gSaA ;fn bu esa ls fdlh dh Hkh deh gks rks Hospital v/kwjk gksrk gSA blh rjg ls Computer Hkh ,d System gS] ftlds fofHkUu vo;o tSls fd Monitor, Mouse, Keyboard, CPU o leL;k dk lek/kku izkIr djus ls lEcaf/kr Application Software vkfn gksrs gSa vkSj ;s lHkh vkil esa feydj fdlh leL;k dk ,d mfpr lek/kku iznku djrs gSaA

Database Management System – DBMS Computer esa fofHkUu izdkj ds Data dks Store o Manage djus ds fy, dqN Standard rjhdksa dks mi;ksx esa yk;k tkrk gS] rkfd Computer }kjk fdlh Hkh le; Accurate o Up-To-Date Information dks izkIr fd;k tk ldsA ftu Standard rjhdksa dks mi;ksx esa ysdj fdlh leL;k ls lEcaf/kr Data dks Manage fd;k tkrk gS] mu rjhdksa ds lewg dks gh Database Management System dgk tkrk gSA fdlh ,d lewg ls lEcaf/kr lwpukvksa dks de ls de txg esa Store djus o Manipulate djus dk lcls vPNk rjhdk ;gh gksrk gS fd ml “Group Of Information” dks ,d lkj.kh ds :i esa Define fd;k tk,A ,d lkj.kh fdlh ,d Group ls lEcaf/kr lwpukvksa dks de ls de txg esa o lcls csgrj rjhds Store djus dk lcls vPNk rjhdk gksrk gSA mnkgj.k ds fy, ekuyks fd gesa fdlh School ds fofHkUu Students dh Information dks Computer ij Manage djuk gks] rks ge ,d lkj.kh cukdj mlesa fofHkUu Students dh tkudkfj;ksa dks NksVs&NksVs VqdMksa ds :i esa fuEukuqlkj Store dj ldrs gSa% //=================================================================



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Sr_No Name Age Sex Class 123 Amit Sharma 15 Male 10 234 Rahul Varma 16 Male 10 121 Salini Bohra 15 Female 9 544 Silpa Roy 14 Female 8 534 Prince Mishra 13 Male 6 532 Devendra Bhati 14 Male 9

//================================================================ ;fn ge bl lkj.kh esa Represent fd, x, lHkh Data dks ,d lkFk ,d Group ds :i esa ns[ksa] rks ge dg ldrs gSa fd ftl Student dk Serial Number 123 gS] mldk uke Amit Sharma gS vkSj mldh mez 15 lky gSA lkFk gh og Class 10th esa i<rk gSA blh rjg ls ge bl lkj.kh esa Represent fd, x, vU; Students dh Hkh fofHkUu izdkj dh tkudkfj;ksa dks izkIr dj ldrs gSaA Database Management System esa blh rjhds dks mi;ksx esa fy;k tkrk gS o leL;k ls lEcaf/kr bdkbZ dh ftu tkudkfj;ksa dks Computer }kjk Manage djuk gksrk gS] mu tkudkfj;ksa dks NksVs&NksVs VqdMksa esa Divide djds] mUgsa Logical Tables esa Data ds :i esa Store dj fy;k tkrk gSA tc ge Computer }kjk fdlh leL;k dks Solve djuk pkgrs gSa] rc lcls igys gesa ml leL;k ls lEcaf/kr mu eq[; Entities dks Identify djuk gksrk gS] ftUgsa ge Computer ij Mange djuk pkgrs gSaA mnkgj.k ds fy, ;fn ge fdlh Student ls lEcaf/kr fofHkUu izdkj dh Information dks Computer }kjk Manage djuk pkgrs gSa] rks bl leL;k ds fy, Student og Entity gksrk gS] tks fd gekjh leL;k ls lEcaf/kr gksrk gSA fdlh leL;k esa gesa”kk dsoy ,d gh Entity gks] ,slk dHkh Hkh t:jh ugha gksrk gSA fofHkUu izdkj dh ifjfLFkfr;ksa esa fdlh leL;k ls lEcaf/kr ,d ls T;knk izdkj ds Entities gks ldrs gSaA nqfu;ka dk dksbZ Hkh O;fDr] oLrq ;k ?kVuk fdlh fo”ks’k ifjfLFkfr esa ,d Entity ds :i esa Identify gks ldrk gSA tc ,d Programmer fdlh Business ls lEcaf/kr Data dks Computer ij Manage djuk pkgrk gS] rc og ftl Organization ds fy, Application Develop dj jgk gksrk gS] ml Organization ds vk/kkj ij ;s r; gksrk gS fd ml Application ls lEcaf/kr eq[; Entities dkSu&dkSu ls gSaA pwafd fofHkUu izdkj ds Organizations fofHkUu izdkj ds dke djrs gSa] blfy, fdlh ,d Organization ds fy, tks O;fDr] oLrq ;k ?kVuk ,d Entity ds :i esa Represent gksrk gS] ogh O;fDr] oLrq ;k ?kVuk fdlh nwljs Organization ds fy, Hkh ,d eq[; Entity gks] ,slk t:jh ugha gksrk gSA mnkgj.k ds fy, fdlh School esa Teaching djokus okyk Teacher ml School ds Database Application ds fy, ,d Employee Entity gksrk gS] ysfdu tc ogh Teacher fdlh Bank esa viuk Account Open djokrk gS] rc ml Bank ds fy, ogh Teacher ,d Customer Entity gks tkrk gSA tc ge Computer esa fdlh Entity dks Represent djuk pkgrs gSa] rc gesa ml Entity dh mu Characteristics dks Identify djuk gksrk gS] ftUgsa ge Computer ij Manage djuk pkgrs gSaA ;s Characteristics gh ml Entity dks Computer esa Represent djus ds ek/;e gksrs gSaA



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nqfu;ka ds gj Object dh viuh dqN fof”k’Vrk,a ;k yk{kf.kdrk,a (Characteristics) gksrh gSa] ftuds dkj.k ge ml Object dks fdlh nwljs Object ls vyx igpku ikrs gSaA pwafd fdlh leL;k ls lEcaf/kr Entity Hkh blh Real World dk dksbZ uk dksbZ Object gksrk gS] blfy, ml Entity dh Hkh viuh dqN Special Characteristics gksrh gSa] ftuls ml Entity dks Identify fd;k tk ldrk gSA Entity dh bu Characteristics dks lkekU;r;k Attributes dgk tkrk gS vkSj ;s Attributes gh os ek/;e gksrs gSa] ftuds }kjk ge leL;k ls lEcaf/kr Entity dks Computer esa Represent djrs gSaA fdlh Hkh Entity dk Attribute. Information dk og lcls NksVk fgLlk gksrk gS] ftls Computer ij Store o Manage fd;k tkuk gksrk gSA bl Attribute dks lkekU;r;k Field dgk tkrk gSA bu Fields esa gesa”kk fdlh uk fdlh izdkj dk eku ;kuh Data Store fd;k tkrk gSA fdlh leL;k ls lEcaf/kr fdlh ,d Entity ds ftu Attributes dks Computer ij Mange djuk gksrk gS] mlh leL;k esa mlh izdkj ds cgqr lkjs Entities ds fy, Hkh mUgha Attributes dks Computer ij Manage djuk gksrk gSA bl fLFkfr esa leku Group ds <sj lkjs Entities leku Attributes dks Share djrs gSa] ftUgsa Computer esa Field }kjk Represent fd;k tkrk gSA fdlh leku Field dks Share djus okys lHkh Entities ds Group dks Entity Set dgk tkrk gSA vc ge ,d mnkgj.k }kjk bl iwjh izfØ;k dks le>us dh dksf”k”k djrs gSaA ekuyks fd fdlh School dk Principal mlds School esa i<us okys lHkh Students dh tkudkfj;ksa dks Computer ij Maintain djuk pkgrk gS] rkfd tc Hkh mls fdlh Particular Student ls lEcaf/kr tkudkfj;ksa dh t:jr gks] og ml Student dk Serial Number ml Student Database Application Software Input djs vkSj Computer ml Student ls lEcaf/kr lHkh Information dks Screen ij Display dj nsA fdlh Hkh Database System Application dks Develop djus ls igys gesa lcls igys leL;k dks vPNh rjg ls Analyze djds ;s irk yxkuk gksrk gS fd vkf[kj ml System dh eq[; vko”;drk D;k gS vkSj ml vko”;drk dks iwjk djus ls lEcaf/kr dqy fdrus Entities gSa o os Entities dkSu&dkSu ls gSa\ pwafd gekjh bl leL;k dks ;fn ge /;ku ls ns[ksa rks bl leL;k dh eq[; Requirement School ds Students dh Information gh gS vkSj leL;k ls lEcaf/kr eq[; Entity Hkh Student gh gSA leL;k ls lEcaf/kr Entity dk irk py tkus ds ckn gesa ;s irk yxkuk gksrk gS] fd ml Entity ls lEcaf/kr fdu ckrksa dks Computer ij Maintain djuk gSA ;s ckrsa gh ml Entity dk Attributes gksrs gSa] ftUgsa Fields ds :i esa Define fd;k tkrk gSA pwafd gekjh bl leL;k esa eq[; Entity Student gS vkSj ,d Student ls lEcaf/kr os tkudkfj;ka ftudk mi;ksx ,d School esa fd;k tkrk gS] leL;k ls lEcaf/kr tkudkfj;ka gSaA fdlh Student dh eq[;r% fuEu tkudkfj;ka gks ldrh gSa] ftUgsa ,d Computer ij Maintain djuk School ds Principal ds fy, mi;ksxh gks ldrk gS% //==================================================================

1 Student dk uke 2 Student ds firk dk uke 3 Student dk Address 4 Student dh City 5 Student dk ftyk 6 Student dh Class



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7 Student dh Date of Birth 8 Student dh School esa Join djus dh Date of Admission 9 Student dh Age 10 Student dk Serial Number

//================================================================== ;s Description fdlh Hkh Student dh Information ds mu NksVs&NksVs VqdMksa (Attributes) dks Represent djrs gSa] ftudh School ds Principal dks t:jr gks ldrh gSA bu Descriptions ds vk/kkj ij gesa fuEukuqlkj fofHkUu Fields izkIr gks ldrs gSa% //==================================================================

1 SerialNumber 2 Name 3 FName 4 Address 5 City 6 District 7 Class 8 DateOfBirth 9 DateOfAdmissiona 10 Age

//================================================================== ;fn ge bu tkudkfj;ksa ds VqdMksa dks Combined :i esa ns[ksa] rks ;s lHkh Files vkil esa feydj fdlh ,d Student ls lEcaf/kr mu tkudkfj;ksa dks Represent djrs gSa] ftudh ,d School ds Principal dks t:jr gks ldrh gSA ;s lHkh Fields gekjh leL;k ls lEcaf/kr Entity ds mu Attributes dks Represent djrs gSa] ftUgsa Computer ij Store o Mange fd;k tkuk gSA ;fn ge bu Fields dks Title ds :i esa Specify djsa o buds uhps buesa Store fd, tkus okys ekuksa (Data) dks Specify djsa] rks gesa fuEukuqlkj Format izkIr gks ldrk gS] tks fd ,d izdkj dh lkj.kh gS%

bu tkudkfj;ksa ds vykok Hkh Student dh fofHkUu izdkj dh vU; tkudkfj;ksa dks Hkh Store djds Manage fd;k tk ldrk gSA ge ns[k ldrs gSa fd fofHkUu Students leku Attributes dks Share dj jgs gSa] blfy, Students ds bl lewg dks Entity Set dgrs gSaA gekjs Entity Set esa dqy 6 Students gSaA bl lkj.kh dk gj Column fdlh Student ds fdlh ,d Attribute ds eku dks Represent dj jgk gSA mnkgj.k ds fy, Name Column gj Student dk dsoy uke Specify djrk gS] blh rjg ls DOB Column gj Student dk Date Of Birth Specify dj jgk gSA ;s fofHkUu Columns fdlh Student Entity ds fofHkUu Attributes ;k Fields dks Specify dj jgs gSaA



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bl lkj.kh ds vk/kkj ij ;fn ge SrNo 001 okys Student dh tkudkjh izkIr djuk pkgsa] rks gesa Left To Right pyrs gq, bl Serial Number okys Student dk uke Rahul izkIr gksrk gS] ftlds firk dk uke Mohan Lal gS vkSj og Falna uke dh City esa jgrk gSA bl City dk District Pali gS vkSj og Class 10th esa i<rk gSA Rahul dh Date Of Birth 10 Feb 1982 gS vkSj mlus bl School esa 15 July 1987 dks Admission fy;k gSA ;kuh ge bl lkj.kh ds vk/kkj ij dg ldrs gSa fd bl lkj.kh ds lHkh Fields vkil esa Logically Related gSa] blh dkj.k ls lHkh Fields vkil esa feydj fdlh ,d Student ls lEcaf/kr lHkh tkudkfj;ka iznku dj jgs gSaA tc cgqr lkjs Fields tks fd vkil esa Logically Related gksa] feydj fdlh ,d Entity ls Related fofHkUu izdkj dh tkudkfj;ka Provide djrs gSa] rks Logically Related Fields ds bl Group dks ,d Record dgk tkrk gSA ;kuh ;fn ge fiNyh lkj.kh ds vk/kkj ij dgssa rks bl lkj.kh dk gj Row ,d Unique Student ds Record dks Specify dj jgk gSA fdlh Record dks Database Management System dh Hkk’kk esa Tuple dgk tkrk gSA tc fdlh leL;k esa ,d ls vf/kd Entities Involved gksrs gSa] rc mu lHkh Entities ds Attributes dks blh izdkj ls izkIr fd;k tkrk gS vkSj blh izdkj ls ,d Table }kjk gj Entity dks Represent fd;k tkrk gSA lkjka”k esa dgsa rks ge dg ldrs gSa fd fdlh leL;k ls lEcaf/kr fofHkUu Entities dh ftu fo”ks’krkvksa dks Computer esa Store djuk gksrk gS] mu fo”ks’krkvksa dks Entity dk Attribute dgk tkrk gS] ftls Database Management System dh Hkk’kk esa Field dgk tkrk gSA fdlh Entity ds Attributes (Data Fields) dk og lewg tks fd vkil esa Logically Related gksrs gSa] fdlh ,d Entity ls lEcaf/kr fofHkUu lwpukvksa dks Specify djrs gSaA bu Logically Related Fields ds lewg dks Record dgk tkrk gS] tks fdlh Entity ds mu Data dks Specify djrk gS] ftUgsa Computer ij Store o Manage fd;k x;k gksrk gSA tc ,d gh izdkj ds cgqr lkjs Entities ;kuh Entity Set ds Data dks Computer ij Store o Manage fd;k tkrk gS] rc bl Entity Set ds lewg dks Table ;k Entity ;k Database Mange System dh Hkk’kk esa Relation gks tkrk gSA ;kuh ljy “kCnksa esa dgsa rks Fields ds lewg dks Record dgrs gSaA Records ds lewg dks Table dgrs gSa vkSj Tables ds lewg dks Database dgrs gSaA

Requirement of Good Database Design vkt ftrus Hkh Businesses Database System ij fuHkZj gSa] ;kuh vius Business ls lEcaf/kr tkudkfj;ksa dks Computer }kjk Manage djrs gSa] os lHkh Accurate o Up-To-Date Information izkIr djus ds fy, gh Computer dk mi;ksx djrs gSaA ftrus Hkh Business Corporations Computer ij vius Business ls lEcaf/kr Data dks Maintain djrs gSa] mu lHkh dks dHkh uk dHkh fdlh uk fdlh :i esa vius Data ds Report dh t:jr gksrh gS] ftlds vk/kkj ij ml Business dks Operate djus okyk Authorizer vius O;olk; ls lEcaf/kr t:jh fu.kZ; ysrk gSA blfy, ;s t:jh gks tkrk gS fd fdlh Hkh Database esa Store fd, tkus okys Data Accurate, Complete o bl rjg ls Well Organized gksus pkfg,] rkfd tc Hkh fdlh izdkj ds Information dh t:jr gks vkSj ftl Format esa Information dh t:jr gks] ml Information ls lEcaf/kr Data dks mlh Format esa Fastly o Accurately izkIr fd;k tk ldsA



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fdlh Hkh Database System dks Develop djrs le; lcls vk/kkjHkwr rF; ds :i esa blh ckr dk /;ku j[kk tkuk gksrk gS] fd Develop fd;k tkus okyk Application pkgs Local Area Network ij Use fd;k tkuk gks ;k fdlh Web Site ls Data dks Access fd;k tkuk gks] nksuksa gh fLFkfr;ksa esa Database ls izkIr gksus okyk Data Accurate o Fast gksuk pkfg,A ;kuh Database pkgs NksVk gks ;k cMk] ;fn ge ,d Database System dks fcuk fdlh ijs”kkuh ds yEcs le; rd ds fy, mi;ksxh cukuk pkgrs gSa] rks gesa Database dks cgqr gh lko/kkuhiwoZd vPNs rjhds ls Design djuk t:jh gksrk gSA ;fn Database dk Design detksj gks] rks pkgs ftruk Hkh vPNk Program Develop dj fy;k tk,] ml Database System ls iSnk gksus okyh ijs”kkfu;ksa ls cpk ugha tk ldrk gSA fdlh Database Management System ls lEcaf/kr Application esa ftruh Hkh ijs”kkfu;ka iSnk gksrh gSa] muesa ls T;knkrj ijs”kkfu;ksa dk dkj.k Database dk [kjkc Design gh gksrk gSA tc fdlh Database System Application dks Develop djrs le; Database ds Design ij lko/kkuhiwoZd T;knk /;ku ugha fn;k tkrk gS] rc Hkfo’; esa ml Application ls lEcaf/kr fofHkUu izdkj dh ijs”kkfu;ksa dk lkeuk djuk iMrk gSA vPNs Database Design dk eryc ;s gS fd ge Database System dks Develop djrs le; i;kZIr le; ysa o lko/kkuhiwoZd Database dks bl rjg ls Design djsa] tks fd Hkfo’; esa de ls de ijs”kkuh iSnk dj ldsA bl izdkj dk Database Design djrs le; gesa bl ckr ij Focus j[kuk gksrk gS] fd ge ftl Organization ls lEcaf/kr Database System Develop dj jgs gSa] ml Organization esa fofHkUu izdkj ds dkeksa dks fdl izdkj ls iwjk fd;k tkrk gSA ;fn Organization ftl rjhds ls dke djrk gS] ml rjhds ls Organization dks Hkfo’; esa fdlh rjg dh ijs”kkuh dk lkeuk ugha djuk iMrk gS] rks fuf”pr :i ls ml Organization ds dke djus ds rjhds ds vk/kkj ij Develop fd;k x;k Database System Hkh Hkfo’; esa fdlh izdkj dh dksbZ ijs”kkuh iSnk ugha djsxkA

Effects of Poor Database Design ,d Database dk Design fdl izdkj ls fdlh Database System Application esa ,d cgqr gh egRoiw.kZ Roll vnka djrk gS] bl ckr dks ge ,d lkekU; ls Business Example }kjk gh le> ldrs gSaA ge tks Business Example ys jgs gSa] mlesa ,d cgqr gh Poor Design dks Use fd;k x;k gS vkSj blh Poor Design ds dkj.k fofHkUu izdkj dh ijs”kkfu;ka Generate gksrh gSa] ftUgsa ,d&,d djds le>k;k x;k gSA bl Business Example dks geus “Music Store” uke fn;k gSA bl Business esa ,d Music Store fofHkUu Titles ds CDs o DVDs dh Selling dk dke djrk gSA ;s Music Store Mail ls vkus okys Orders ds vk/kkj ij Titles Selling dk dke djrk gSA bl Business Example esa tc Hkh dksbZ Customer fdlh Single Item dks Purchase djus ds fy, Order nsrk gS] Music Store dk ,d Employee fuEu Form dks Fill djds Customer ds Order dks Computer ij Data ds :i esa Store ;k Record dj ysrk gSA



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pwafd ge ;s eku jgs gSa fd Music Store ij vkus okys Orders Mail }kjk vkrs gSa] blfy, ,d gh City ls dbZ Customers Orders vk ldrs gSaA bl Music Store Software esa gj Customer dks Uniquely Identify djus ds fy, ,d Unique Number Assign fd;k x;k gSA gj Customer dk Unique Customer Number Create djus ds fy, gj Customer ds Pincode Number ds lkFk mlds uke ds igys rhu Character dks Use fd;k tkrk gS vkSj uke ds ckn rhu Digit dk ,d Sequence Number Specify fd;k tkrk gSA ;kuh ;fn Krishna uke dk dksbZ Customer fdlh Item ds fy, bl Music Store ij dksbZ Order nsrk gS vkSj og Customer 123456 Pincode Number okys “kgj esa jgrk gS] rks ml Customer dks Identify djus ds fy, cuus okyk Customer Code 123456KRI001 gksxkA Sequence Number bl ckr dh iqf’V djrk gS fd ,d gh “kgj esa jgus okys ,d gh uke ds nks Customer dks Hkh Music Store }kjk Uniquely Identify fd;k tk ldrk gSA tc Music Store esa Titles Distributor ls dksbZ u;k Title vkrk gS] rks Music Store dk ,d Employee mu lHkh Customers dks Search djrk gS] ftUgksaus ml Title ds fy, igys ls gh Order ns j[kk FkkA fQj og Employee mu Customers dh Computer esa Stored Order Data ds vk/kkj ,d List Create djrk gS vkSj Form ij fLFkr “Item shipped?” Check Box esa ,d ‘X’ Place dj nsrk gS] tks bl ckr dk Signal gksrk gS fd igys ls vk, gq, Order dks iwjk dj fn;k x;k gSA igyh utj esa ns[kus ij Music Store dk ;s Management dkQh lkQ lqFkjk o ljy yxrk gSA FkksMs le; rd ;s Software dke Hkh Bhd rjg ls djrk gSA ysfdu ,d&nks lky ckn bl Software ls Serious Problems iSnk gksus yxrh gSaA

Unnecessary Duplicated Data and Data Consistency Music Store Database esa cgqr lkjk Data ckj&ckj vuko”;d :i ls Duplicated Form esa Input djuk iMrk gS vkSj ,d gh izdkj ds Data dks ckj&ckj fdlh Database esa Store djus ls fofHkUu izdkj dh leL;k,a iSnk gksrh gSa] ftlls Database dks Manage djuk dfBu gks tkrk gSA fdlh Database esa ,d gh izdkj ds Data dks ckj&ckj Store djus dh izfØ;k dks Data Redundancy dgk tkrk gSA tc Hkh dksbZ Customer Music Store ij dksbZ Title Order djrk gS] mijksDr Form esa ml



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Customer ds Order dks Record dj fy;k tkrk gSA fdl Customer us dkSulk Order Place fd;k gS] bl ckr dh tkudkjh j[kus ds fy, Order nsus okys Customer dk uke] Address o Phone Number Hkh Order dh Information ds lkFk gh Database esa Store dj fy;k tkrk gSA vc pwafd ,d gh Customer ,d ls T;knk ckj Order dj ldrk gS] blfy, dksbZ ,d gh Customer ftruh ckj Hkh fdlh Title ds fy, Music Store ij Order nsrk gS] gj ckj ml Customer ds uke] Address o Phone Number dks Form ij Fill djds Order dh Information ds lkFk Database esa Store dj fy;k tkrk gSA ftlls ml Customer dh Information dk ckj&ckj Duplication gksrk gSA tc gekjs Database esa bl rjg ls Duplicated Form esa Data Store gks jgs gksrs gSa] rc gesa bl ckr dk /;ku j[kuk t:jh gks tkrk gS fd Duplication Form esa Store gksus okys lHkh Data gj ckj leku :i esa gh Database esa Store gksaA nwljs “kCnksa esa dgsa] rks fdlh Customer }kjk fn, tkus okys gj Order dks Music Store Application esa Store djrs le; gesa bl ckr dk /;ku j[kuk t:jh gksrk gS fd ml Customer ds gj Order esa mldk uke] Address o Phone Number ,d tSls gh Store fd, tk,A blh rjg ls ,d Single Title ds fy, ftrus Hkh Order Place fd, tkrs gSa] mu lHkh Orders esa Title dks ,d Hkh Character ds gsj&Qsj ds fcuk ,d tSlk Type djuk t:jh gksrk gSA blh iwjh izfØ;k ds dkj.k Input fd;k tkus okyk Duplicated Data Consistent (fo”oluh;) gks tkrk gSA tSls&tSls Database dk Data c<rk tkrk gS] bl izdkj dh Constancy dks Maintain djuk dkQh eqf”dy gks tkrk gSA T;knkrj Business Oriented Database Software Case Sensitive gksrs gSa] ftuesa Uppercase Letters o Lowercase Letters vyx&vyx Behave djrs gSaA ge ;s eku ldrs gSa fd Music Store Form esa Order dh Entry djus okyk dksbZ Hkh Operator bruk Perfect Typist ugha gks ldrk] tks gesa”kk bl ckr dks /;ku j[k lds fd mlus fdl Customer ds uke o irs esa dkSulk Character Capital Letter esa fy[kk Fkk vkSj dkSulk Character Small Letters esaA bl fLFkfr esa fdlh ,d gh Customer ds Orders dh Entry djrs le; ;fn ,d Hkh Character ds Typing dk Difference gks x;k] rks Database Software ,d gh Customer ds nks vyx Unique Record Create dj ldrk gSA mnkgj.k ds fy, ekuyks fd “Rahul” o “Rohit” uke ds nks Customers “UMI 10” uke ds Title dh DVD dk Order Music Store ij Place djrs gSaA Typist tc bu nksuksa Orders dks Music Store Application ds Form }kjk Database esa Store djrk gS] rc og “Rahul” dk Order Specify djrs le; Title ds LFkku ij “UMI 10” Character Combination dk iz;ksx djrk gS] tcfd “Rohit” dk Order Specify djrs le; Title ds LFkku ij “UMI10” Character Combination dk iz;ksx djrk gSA vc ekuyks fd Music Store dks mu Customers dh tkudkjh izkIr djus dh t:jr iMrh gS] ftUgksaus “UMI 10” uke ds Album dk Order fn;k gSA Music Store Software ls bl ckr dh tkudkjh izkIr djus ds fy, ;fn Typist “UMI10” Character Combination dk iz;ksx djrk gS] rks Application }kjk Generate gksus okyh Pending Orders dh List esa “Rahul” dk



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Order Display ugha gksxk vkSj ;fn Typist “UMI 10” Character Combination dk iz;ksx djrk gS] rks “Rohit” dk Order Display ugha gksxkA bl fLFkfr esa ge le> ldrs gSa fd “Rahul” o “Rohit” nksuksa esa ls fdlh ,d ds Pending Order dh gh tkudkjh ;s Music Store Application ns ldrk gSA ftlls fdlh uk fdlh Customer ds Order dh Request rks v/kwjh gh jgsxhA gekjs Current “Music Store” Application esa bl ckr dks Ensure djus dh dksbZ O;oLFkk ugha gS fd Database esa Data Hkys gh Duplicated Form esa Store gksa] ysfdu Duplicated Data Hkh Consisted Form ;kuh fo”oluh; :i ls Database esa Enter gksaxs vkSj mijksDr izdkj dh leL;k,a Generate ugha gksaxhA bl izdkj dh leL;kvksa dks Solve djus ds fy, nks rjhds mi;ksx esa fy, tk ldrs gSa% igyk rjhdk ;s gS fd Data Duplication dks ftruk gks lds mruk jksdk tk,A bl Solution ds ckjs esa ge vkxs vkSj vPNh rjg ls le>saxsA ysfdu ;gka ;s tku ysuk t:jh gksxk fd fdlh Hkh Database Application esa Data dh Redundancy ;kuh Duplication dks iwjh rjg ls Eliminate djuk uk rks lEHko gS vkSj uk gh bldh t:jr gksrh gSA ;kuh gj Database esa FkksMk cgqr Data Duplication rks gksrk gh gS] tks fd fdlh Hkh Database dks Bhd ls Manage djus ds fy, t:jh Hkh gksrk gSA nwljk rjhdk ;s gS fd tc Hkh fdlh Order dh Entry Database esa gks] rks dksbZ ,slk rjhdk gksuk pkfg,] tks ;s Verify dj lds fd tc Data Duplicate Form esa Enter gks] rc Data gesa”kk ,d gh izdkj ls Database esa Store gksA ,d Well Design Database esa bu nksuksa Solutions dks Use fd;k tkrk gSA Duplication ls iSnk gksus okyh nwljh leL;k ;s gS fd ,d gh Information dks ckj&ckj Store djus ls Database dh Size c< tkrh gS] D;ksafd ,d gh izdkj ds Data, Store gksus ds fy, Memory esa ckj&ckj Storage Space ysrs gSaSA ysfdu pwafd vkt Disk Space mruh egaxh ugha gS] ftruh igys gqvk djrh Fkh] blfy, vkt Storage Space dh cpr ds fy, Redundant Data dks Eliminate djuk mruk cMk dkj.k ugha gS] ftruk Database dks ljyrk ls Maintain djukA

Data Insertion Problems Music Store tSls ftrus Hkh Database gksrs gSa] tSls fd Publication vkfn] buesa ftrus Hkh Titles gksrs gSa] mudh ,d List curh gS] ftlds }kjk ;s irk pyrk gS fd ml Music Store ;k Publication ij fdu&fdu Titles ds Items miyC/k gSaA mnkgj.k ds fy, tc Hkh fdlh u, Title dh CD/DVD Market esa vkus okyh gksrh gS] bu Music Store ij ml u, Title dks vius Catalog esa Add djuk gksrk gSA Bhd blh rjg ls fdlh Publication esa tc Hkh dksbZ ubZ Book Publish gksrh gS] ml Publication dks Hkh vius Catalog dks Update djuk iMrk gSA ,slk blfy, fd;k tkrk gS rkfd Music Store ;k Book Store ds Customers bl u, Title dks Advance esa Order dj ldsaA Catalog ,d ,slh List gksrh gS] ftlesa dksbZ Music Store ;k Publication vius Items dh List dks Store djrk gS] rkfd og vius Customers dks bl ckr dh tkudkjh ns lds fd



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mlds ikl dkSu&dkSu ls Title ds Item miyC/k gSaA pwafd ge ftl Music Store Application dks mnkgj.k ds :i esa mi;ksx esa ys jgs gSa] mlesa fofHkUu Titles ds Catalog dks Maintain djus dh dksbZ O;oLFkk ugha gS] blfy, tc Hkh Market esa fdlh u, Title ds vkus dh lwpuk feyrh gS] bl Music Store esa ,d Employee Lo;a vius Catalog dks Update djrk gS vkSj vius Titles ds Updated Booklet dks vius gj Customer dks Hkst nsrk gS] rkfd mudk Customer ;s r; dj lds fd mls dkSu&dkSu ls Title Order djus gSaA bl Catalog Booklet esa cgqr lkjs Pages gks ldrs gSa vkSj gj Page dks Music Store dk dksbZ Employee Lo;a “Copy Paste” dh izfØ;k }kjk rS;kj djrk gSA vc ekuyks fd ge ;s pkgrs gSa fd ;s Catalog Booklet Database ds vk/kkj ij Lo;a gh rS;kj gks tk,A pwafd fofHkUu izdkj ds Titles Database esa Stored gksrs gSa] blfy, ge Catalog Booklet dks Database ds vk/kkj ij rS;kj dj ldrs gSaA ysfdu fQj Hkh ge Current Database ds vk/kkj ij ;s dke ugha dj ldrs gSaaA blds nks dkj.k gSa% fdlh Hkh Catalog esa fdlh Hkh Title ls lEcaf/kr fofHkUu izdkj dh Additional tkudkfj;ka gksrh gSaA mnkgj.k ds fy, fdlh Title ds Singer, Music Director, Financer vkfn dh tkudkfj;ka gks ldrh gSa vkSj Title ls lEcaf/kr dqN Extra Description gks ldrh gSaA pwafd gekjs Music Store Database esa bu tkudkfj;ksa dks Store djus dh O;oLFkk ugha gS] blfy, bl leL;k ds lek/kku ds :i esa ge gekjs Music Store ds Database dks Modify djds mlesa u, Fields Create dj ldrs gSaA ysfdu ;s rjhdk Hkh iwjh rjg ls Catalog Create djus esa l{ke ugha gks ldrkA D;ksafd ,d gh Title dks cgqr lkjs Customers Order dj ldrs gSaA bl fLFkfr esa gj Order ds lkFk Title dh fofHkUu Descriptions dks Computer esa Store djus ls Data dh Redundancy c< tk,xh vkSj ;fn dsoy ,d gh Customer ds Order esa fdlh Title dh Information dks Store fd;k tk, rks gesa”kk bl ckr dks /;ku j[kuk gksxk fd fdl Title dh Extra tkudkfj;ksa dks fdl Customer ds Order esa Specify fd;k x;k gS] tks fd ,d ukeqefdu dke gSA nwljh leL;k ;s gS fd gekjs Music Store Application ds Database Management System esa ,slh dksbZ O;oLFkk ugha gS] ftlls fdlh Title dks Advance esa gh Database esa Enter fd;k tk ldsA tc rd dksbZ Customer ml u, Title dk Order Place ugha djrk gS] rc rd ml Title dks Database esa Store ugha fd;k tk ldrk gS vkSj tc rd Title Database esa Store ugha gksxk] rc rd Updated Catalog Booklet Create ugha fd;k tk ldrkA lkFk gh Customer rc rd ml Title dk Order Place ugha dj ldrk tc rd fd mls Updated Catalog Booklet izkIr uk gks] D;ksafd mls u, Title dh tkudkjh Updated Catalog Booklet ls gh izkIr gksrh gSA bl leL;k dks Database Management dh Hkk’kk esa “Insertion Anomaly” dgk tkrk gSA

Data Deletion Problems gekjs bl Music Store Database Program ls tc fdlh Data dks Delete fd;k tkrk gS] rc Hkh dqN leL;k,a lkeus vkrh gSaA ekuyks fd ,d Customer dsoy ,d Item dk Order nsrk gSA Order dks Process djus ds ckn ;kuh Order dh Entry Music Store ds Form }kjk Database esa dj nsus ds ckn irk pyrk gS fd ml Item dks Manufacture djus okys



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Manufacturer us ml Item dks Create djuk cUn dj fn;k gSA bl fLFkfr esa Music Store vius fdlh Hkh Customer dks og Item ugha Hkst ldrk] ftlus bl Out Of Stock Item ds fy, Order fd;k gSA vc pwafd Orders dh Entry Database esa igys gksrh gS] blfy, mu lHkh Customers ds Order dh List esa ls bl Item dk Reference Database ls Delete djuk gksxk] ftUgksaus ml Particular Item ds fy, Order fd;k gS] tks fd vc Available ugha gSA pwafd ftu yksxksa us cgqr lkjs Items Order fd, gSa] muds Order dh List esa ls dsoy bl Unavailable Item ds Reference dks Delete djuk gksxk] tcfd ftu yksxksa us dsoy blh Item dk Order fd;k Fkk] Database ls muds Order dh List esa ls bl Item dk Reference Delete djus ij muds Order esa dksbZ Item ugha cpsxk] ftls ml Customer dks Hkstk tk ldsA bl fLFkfr esa ,sls Customers dk Order Hkh Delete dj fn;k tk,xkA vc pwafd fofHkUu Customers dh Information Hkh muds Order ds lkFk gh Database esa Store gksrh gS] blfy, ;fn fdlh Customer us ml Unavailable Item ds fy, Music Store dks First Time Order fn;k gks] rks tc ml Customer dk Order Delete gksxk] ml Order ds lkFk gh ml Customer dh Information Hkh Delete gks tk,xhA bl fLFkfr esa Music Store ml Customer dks Hkfo’; esa dksbZ Catalog Booklet ugha Hkst ldsxk vkSj Music Store dk ml Customer ls Link gh VwV tk,xk] D;ksafd ml Customer dk Address mlds Un-Fulfilled Order ds lkFk gh Delete gks pqdk gSA Database dh bl Problem dks Database dh Hkk’kk esa “Deletion Anomaly” dgrs gSaA

Meaningful Identifiers gekjs Database esa ,d vkSj cMh leL;k gS tks fd Customer dks Uniquely Identify djus ds fy, Create fd, tkus okys Customer Number dh gSA bl Database esa fdlh Hkh Customer dks Uniquely Identify djus ds fy, ,d fo”ks’k rjhds dks Use fd;k x;k gS] ftlesa ml Customer ds uke o City ds Pincode Number dks Use fd;k tkrk gSA vc ekuyks fd ,d Customer ftl City esa jgrk gS] ml City dks NksMdj fdlh nwljs “kgj esa pyk tkrk gSA bl fLFkfr esa mlh Customer dks Identify djus ds fy, fQj ls ,d u;k Customer Number Create fd;k tk,xk] tks fd ml nwljh City ls lEcaf/kr gksxkA ftlls gekjs bl Database esa ,d gh Customer ds nks ID gks tk,axs tks ,d gh Customer dks Refer djsaxsA ekuyks fd ,d Customer Music Store ij ,d Order Place djrk gS vkSj mlds ckn og viuh City Change dj ysrk gSA vc ;fn og Customer viuh City Change dj ysus ds ckn ;s tkuuk pkgrk gS fd mlds fdrus Order Music Store ij Pending gSa] ftlds Items dks Music Store us ml Customer dks Serve ugha fd;k gSA ml Customer ds Pending Orders dh tkudkjh izkIr djus ds fy, Music Store dk og Operator tks fd Music Store Software dks Operate djrk gS] ml Customer ls mldk Customer Number iwNsxk] rkfd og ml Customer Number okys Customer dh dqy Transactions dh List izkIr dj ldsA pwafd Customer vc nwljs “kgj esa jgrk gS] blfy, mldk Customer Number Change gks x;k gSA bl fLFkfr esa og vius Current Customer Number dh tkudkjh ml Operator dks nsxkA ftldk eryc ;s gS fd bl “kgj esa vkus ls igys mlus Music Store ij ftrus Hkh Order Place fd, gSa] mudh tkudkjh mls mlds Current Customer Number }kjk izkIr ugha



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gksxh] D;ksafd os Orders mlus vius iqjkus “kgj ls fn, Fks vkSj ml “kgj esa jgus ds dkj.k mldk Customer Number nwljk FkkA bl fLFkfr esa og Customer ;s eku ldrk gS fd mldk Order Music Store dks izkIr ugha gqvkA blfy, og Customer mlh Order dks fQj ls Music Store ij Place dj nsxkA bl fLFkfr esa ,d gh Customer ds ,d gh Order dh nks Entry Music Store Database esa gks tk,xh vkSj tc mu nksuksa Orders dks Music Store }kjk iwjk fd;k tk,xk] rc ,d gh Customer dks leku Items dh nks Copies izkIr gks tk,axh] ftldh nwljh Copy dks lEHkor;k og Customer fQj ls Music Store dks Return dj nsxk vkSj Music Store dks Transportation Charges Lo;a ogua djus gksaxsA

Entities and Data Relationships Database og LFkku gksrk gS] ftlesa Data dks uk dsoy Store fd;k tkrk gS] cfYd mu Store gksus okys Data ds chp dh vkilh Relationship dh Information dks Hkh Store fd;k tkrk gSA Database ds Concept dk eq[; vk/kkj ;s gS fd fdlh leL;k ls lEcaf/kr tkudkfj;ksa dks pkgs cgqr lkjs User Access dj jgs gksa ;k fQj pkgs ,d User Access dj jgk gks] User dks bl ckr dh fpUrk djus dh t:jr ugha gskrh gS fd leL;k ls lEcaf/kr fofHkUu izdkj ds Data Computer esa fdl izdkj ls Store gks jgs gSaA User vius Database ls fofHkUu izdkj ds Data dks dsoy mudh Relationship ds vk/kkj ij Access djds fofHkUu izdkj dh Database Related Information Generate djrk gSA gkykafd User vius Data dks Logically Access djrk gS tcfd Data okLro esa Physically Store gksrs gSaA blfy, User o Database ds chp ds vkilh Conversation dks ,d nwljs Form esa Translate djds ,d nwljs dks Available djokus dk dke ,d Software djrk gS] ftls Database Management System Software (DBMS) dgk tkrk gSA ge ftl Formal Way dks Use djds fofHkUu izdkj ds Data Relationship fdlh DBMS Software dks Express djrs gSa] ml Formal rjhds dks Data Model dgk tkrk gSA ge ftl Relational Data Model dks bl iqLrd esa i<saxs] og dsoy ,d Formal Structure gh gksrk gSA blls igys fd ge fdlh Database dks Design djsa] gesa Store fd, tkus okys fofHkUu izdkj ds Data ds chp dh vkilh Relationships dks Identify djuk gksrk gSA lkekU;r;k fofHkUu izdkj ds DBMS Softwares dsoy ,d gh Data Model dks Support djrs gSaA blfy, tc ge fdlh DBMS Software dks Choose dj jgs gksrs gSa] rc ge okLro esa vius Data Model dks Hkh Choose dj jgs gksrs gSaA

Entities and Their Attributes og pht ftldh tkudkfj;ksa dks ge Data ds :i esa fdlh Database esa Store djrs gSa] Entity dgykrk gSA gekjs Music Store Application ds lEca/k esa Customer ,d izdkj dk Entity gS D;ksafd ge Customer ls Related Data dks Database esa Store djrs gSaA Entity gesa”kk dksbZ Physical oLrq gh gks] ,slk t:jh ugha gksrk gSA nqfu;ka dh fdlh Hkh ml oLrq dks Hkh ge Entity eku ldrs gSa] tks fd fdlh Physical Entity ls Related gksA mnkgj.k ds fy, fdlh Bank dk Account Hkh ,d Entity gks ldrk gS] D;ksafd og ,d Physical Person ls gh lEcaf/kr gksrk gSA gj Entity ds dqN Data gksrs gSa] tks ml Entity dks Describe djrs gSaA Entity ds bu Data



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dks Entity dk Attribute dgk tkrk gSA mnkgj.k ds fy, gekjs Music Store Application ds lEca/k esa ,d Customer dks mlds Customer Number, First Name, Last Name, Street, City, State, Pincode o Phone Number }kjk Describe fd;k tkrk gSA blfy, ;s lHkh Data Customer Entity ds Attributes gSaA tc ge fdlh Database esa fdlh Entity dks Represent dj jgs gksrs gSa] rc okLro esa ge fdlh Entity ds dsoy Attributes dks gh Computer esa Store dj jgs gksrs gSaA Attributes dk gjsd Group tks fd fdlh ,d Single Real World Entity ds ,d mnkgj.k dks Describe djrk gS] ogh Attributes dk Group ml Entity ds nqfu;ka fd fdlh Hkh vU; Instance dks Represent dj ldrk gSA ;kuh tks Attributes fdlh Rahul uke ds Customer dks Represent dj ldrs gSa] os gh Attributes Rohit uke ds fdlh nwljs Customer dks Hkh Represent dj ldrs gSaA mnkgj.k ds fy, Students Entity dh fuEu lkj.kh esa pkj Student Instance gSa vkSj lHkh Instance leku Attributes dks Share dj jgs gSaA //================================================================== SrNo Name FName Add Dist. Class DOB DOA //================================================================== 001 Rahul Mohan Lal Falna Pali 10 10-02-1982 15-7-1987 002 Rohit Sohan Lal Bali Pali 09 11-12-1983 05-7-1987 003 Krishna Gopal Desuri Pali 08 20-03-1981 10-7-1987 004 Madhav Ram Lal Falna Pali 10 30-2-1982 01-7-1987 //================================================================== ;fn gekjs bl Database esa 2000 Students gksrs] rks bl lkj.kh }kjk 2000 Students Attributes ds Collections gksrsA

Entity Identifiers fdlh Entity dks Describe djus okys fofHkUu Data dks Database esa Store djus dk eq[; Purpose ;gh gS fd bUgsa ckn esa fdlh Information dks Retrieve djus ds fy, Use fd;k tk,xkA bldk eryc ;s gqvk fd gesa fdlh uk fdlh rjhds ls fdlh ,d Entity dks fdlh nwljs Entity ls vyx Represent djuk gksxk rkfd ge bl ckr ds fy, Ensure gks ldsa] fd ge ftl Entity ds Data dks izkIr djuk pkgrs gSa] gesa mlh Entity ds Data izkIr gksaxsA mnkgj.k ds fy, ekuyks fd Music Store ds Database esa Krishna uke ds nks Customers gSaA vc ;fn Krishna uke ds Customer ds Order dh tkudkjh izkIr djus ds fy, Music Store esa Searching dh tk,] rks Music Store Application fdl Krishna ds Data Return djsxk\ pwafd nksuksa Customers ds uke leku gSa] blfy, Music Store Application nksuksa gh Customers ds Orders dh List dks Display djsxkA D;ksafd gekjs bl Application esa ,slk dksbZ rjhdk Use ugha fd;k x;k gS] ftlls Music Store Application okafNr Customer ds Orders dh gh List Display djsA bl fLFkfr esa Music Store }kjk Return fd;k tkus okyk Resultant Output Inaccurate gksxkA Music Store Application esa bl leL;k ds lek/kku ds :i esa gj Customer dks ,d Unique



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Customer Number iznku fd;k x;k gS vkSj tc Hkh fdlh Customer ds Orders dh tkudkjh izkIr djuh gksrh gS] rc ml Customer ds uke ds LFkku ij mlds Customer Number dk iz;ksx fd;k tkrk gSA Entities ds Groups esa ls fdlh Particular Entity dks Identify djus dk ;s ,d cgqr gh Common rjhdk gS] D;ksafd fdlh Hkh Database esa nks Customers dks ,d gh Customer Number iznku ugha fd;k tkrk gSA Particular Entity Instance dks Identify djus ds fy, ge ,d nwljk rjhdk Hkh Use dj ldrs gSa] ftlesa fdlh Customer ds First Name o Last Name dks mlds Telephone Number ds lkFk ifjHkkf’kr dj ldrs gSaA fdlh Entity ds bu Attributes ds Combination }kjk Hkh Customer dks Uniquely Identify fd;k tk ldrk gSA ysfdu bl rjhds esa Hkh nks leL;k,a gSaA igyh ;s fd tc Identifier cMk o Tricky gksrk gS] rc blds fdlh Hkh fgLls dks Database esa Enter djrs le; Mistakes gks ldrh gSaA nwljh leL;k ;s gS fd fdlh Hkh Customer dk Phone Number Change gks ldrk gS] ftlls ml Customer dk Identifier Hkh Change djuk gksxk vkSj bl fLFkfr esa ,d gh Customer ds nks Identifier gks tk,axs rFkk ,d gh Customer ds nks Identifier gksus dh fLFkfr esa iSnk gksus okyh leL;kvksa ds ckjs esa ge igys gh i< pqds gSaA dqN Entities tSls fd Invoices vkfn gesa”kk Natural Identifiers ls Represent gksrs gSa] ftls Invoice Number dgk tkrk gSA bl Invoice esa Invoice Number dk dksbZ fo”ks’k vFkZ ugha gksrk gS] ysfdu fQj Hkh bl Invoice Number }kjk fdlh Hkh Invoice dks Uniquely Identify fd;k tkrk gSA Bhd blh rjg ls ge fdlh Hkh Entity dks Uniquely Identify djus ds fy, ,d Meaningless Number dk iz;ksx dj ldrs gSaA mnkgj.k ds fy, fdlh Customer dks Identify djus ds fy, gesa mlds fdlh Attribute ;k Attribute ds Combination dks Use djus dh t:jr ugha gSA ge fdlh Customer dks ,d Meaningless Number }kjk Hkh Identify dj ldrs gSa vkSj tc ge ,slk djrs gSa] rc Customer pkgs dgha Hkh jgs] mlds fdlh Hkh Attribute esa pkgs tks Changes vk,] ml Customer dk Identifier Change ugha gksrk vkSj fdlh Customer dk Identifier Change gksus dh fLFkfr esa iSnk gksus okyh ijs”kkfu;ka Hkh Generate ugha gksrh gSA ge ftruh ckj Hkh fdlh Entity ds ,d Instance dks Database esa Store djrs gSa] ge ;gh pkgrs gSa fd DBMS bl ckr dks Ensure djs fd gj u, Instance dk ,d Unique Identifier gksxkA ;s Concept Database Constraint dk ,d mnkgj.k gSA Constraint ,d ,slk fu;e ;k Rule gksrk gS] ftls Database Follow djrk gSA Database esa fofHkUu izdkj ds Constraints dks ykxw dj nsus ij Database mu Constraints ;k fu;eksa dk ikyu djrk gS] ftlls Database esa Data ds Accurately o Consistently Store gksus dh Guarantee gks tkrh gSA

Single-Valued and Multi-Valued Attributes pwafd ge ,d Relational Database Design dj jgs gSa] blfy, gekjs Data Model esa gj Attribute Single-Valued gksuk t:jh gksrk gSA bldk eryc ;s gqvk fd fdlh Entity ds fdlh Instance ds gj Attribute esa dsoy ,d gh eku (Data) dks Store fd;k tk ldrk gSA mnkgj.k ds fy, dksbZ Customer Entity vius fdlh Hkh Instance dks dsoy ,d Telephone Number Store djus dh lqfo/kk nsrk gSA ;kuh ge fdlh Hkh Customer dk dsoy ,d gh



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Telephone Number Customer Table esa Store dj ldrs gSaA ysfdu fdlh Customer ds ikl ,d ls T;knk Telephone gks ldrs gSaA ;fn ,d Customer ds ikl ,d ls T;knk Phone gSa vkSj og mu lHkh Numbers dks Database esa Include djokuk pkgrk gS] rks Customer Entity ;kuh Customer Table esa fdlh ,d Telephone Attribute File esa ,d ls T;knk Telephone Numbers dks Store ugha fd;k tk ldrk gSA bl fLFkfr dks Customer Entity Handle ugha dj ldrk gSA gkykafd fdlh Database dk Entity-Relationship Model Database dks Represent djus okys Formal ;k Logical Data Model ls vyx ;k Independent gksrk gS] fQj Hkh ge Data ds Entity-Relationship Model dks Data ds Logical Model ds vk/kkj ij gh Develop djrs gSaA pwafd ge Logical Model esa fdlh Attribute esa Multi-Valued eku dks Store ugha djrs gSa] blhfy, ge Entity-Relationship Create djrs le; Hkh fdlh Single Attribute Field esa ,d ls T;knk Data ;k ekuksa dks Store ugha djrs gSaA ,d ls T;knk Phone Numbers dh mifLFkfr Customer ds Table ;k Customer Entity ds Phone Number Attribute dks ,d Multi-Valued Attribute ds :i esa ifjHkkf’kr dj nsrk gSA D;ksafd fdlh Relational Database esa fdlh Hkh Attribute Multi-Valued ugha gksrk gS] blfy, gesa bu Multivalued Attributes dks ,d u;k Entity Create djds Handle djuk gksrk gS vkSj fofHkUu Multi-Valued ekuksa dks ml u, Entity esa Hold djuk gksrk gSA ,d ls T;knk Phone Number gksus dh fLFkfr esa ge Phone Number uke dk ,d Entity Create dj ldrs gSaA bl Entity ds gj Instance esa ,d Attribute ml Customer Number dk gksxk] ftldk Phone Number Store fd;k tkuk gS vkSj nwljk Attribute ml Customer ds Phone Numbers dk gksxkA ;fn fdlh Customer ds pkj Phone Numbers gksa] rks bl Entity esa ml Customer ds pkj Instance gksaxs] ftuesa Customer Number rks leku gksxk ysfdu Phone Numbers vyx&vyx gksaxsA bl Concept dks ge fuEukuqlkj Represent dj ldrs gSa] tgka igyk Entity ,d Customer Entity gS ftlesa pkj Customer Instance gSa tcfd nwljk Entity ,d Phone Number Entity gS] ftlesa gj Customer ds ,d ls T;knk Phone Numbers mlds Customer Number ds lkFk Stored gSaA Customer Entity //================================================================== CustID FName LName City Dist. State //================================================================== 001 Rahul Sharma Falna Pali Rajasthan 002 Rohit Verma Bali Pali Rajasthan 003 Krishna Gopal Beawer Ajmer Rajasthan 004 Madhav Singh Bhyender Thana Maharastra //================================================================== Telephone Entity //================================================================== CustID PhoneNumber //==================================================================

001 9896589360 001 02934223366



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001 02934223654 002 02938222333 003 02937236598 003 9979455505 004 9357268933

//================================================================== Telephone Number Entity esa Telephone Numbers dks Entity Identifier ds :i esa Use fd;k tk ldrk gSA blls Database esa fdlh izdkj dh dksbZ ijs”kkuh iSnk ugha gksrh gSA D;ksafd bl Entity esa ge dsoy Phone Numbers dks gh Store dj jgs gSa vkSj ,d Phone Number vius vki esa Unique gksrk gSA tks Phone Number fdlh Customer Number 001 ds ikl gS ogh Phone Number fdlh Customer Number 003 ds ikl ugha gks ldrkA Multi-Valued Attributes ds lkFk leL;k ;s gksrh gS fd ;fn ge fdlh Entity esa Multi-Valued Attributes dks Store djuk pkgsa] rks gesa gj Value ds fy, ,d u;k Field Create djuk gksxkA ;fn ge u, Fields Create dj Hkh ysrs gSa] rc Hkh ;s dHkh Hkh fuf”pr ugha fd;k tk ldrk fd gesa dqy fdrus u, Fields Create djus pkfg,A D;ksafd fdlh Customer ds ikl fdrus Phone Numbers gks ldrs gSa] ge bl ckr dks dHkh Hkh fuf”pr ugha dj ldrs gSaA mnkgj.k ds fy, ;fn ge gekjs Database esa fdlh Customer ds vf/kdre 4 Phone Numbers Store dj ldus dh lqfo/kk izkIr djus ds fy, fuEukuqlkj Entity dks Design djrs gSa% Customer Entity //================================================================== CustID FName LName ... Phone01 Phone02 Phone03 Phone04 //================================================================== 001 Rahul Sharma ... 223355 445566 442255 002 Rohit Verma ... 121245 235689 214565 568996 003 Krishna Gopal ... 556688 004 Madhav Singh ... 558899 445566 //================================================================== bl Entity Representation esa ge ns[k ldrs gSa fd dsoy Customer Number 002 gh ,slk Customer gS] ftlds ikl pkj Phone gSa vkSj dsoy blh Customer }kjk Phone Numbers ds fy, Reserve fd, x, Storage Space dk mi;ksx fd;k tk jgk gSA “ks’k Customers ds ikl pwafd pkj Phone ugha gSa] blfy, muds bu Attributes }kjk Reserve fd, x, Space dk dksbZ mi;ksx ugha gks jgk gSA ;fn ge ;s eku ysa fd Customer Number 001 ,d vkSj Phone ys ysrk gS] rks ml ikapos Phone Number dks Store djus ds fy, Entity ds Database Representation dks ;kuh Entity dh Table dks Modify djds ,d vkSj u;k Field Customer Table esa Add djuk gksxk] tks fd ,d cgqr gh tfVy dke gksrk gS vkSj fdlh leL;k dks Solve djus ds fy, gesa”kk Database ds Structure dks Change djuk Hkh lEHko ugha gksrk gS] D;ksafd ,slk djus ij Database ds lkFk Connected Front-End Forms dks Hkh iwjh rjg ls Change djuk iMrk gSA ;kuh ge bl rjhds dks rks fdlh Hkh rjg ls Apply ugha dj ldrs gSaA tcfd ge le> ldrs gSa fd T;knkrj yksxksa ds ikl ,d ;k nks gh Phone gksrs gSa] bl fLFkfr esa ;fn ge bl rjhds dks Use djrs Hkh gSa] rc Hkh T;knkrj Customers ds ikl dsoy ,d ;k nks Phone gh gksus dh otg ls bu Attributes ds fy, Reserved Space dk dksbZ mi;ksx ugha



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gksrk vkSj T;knkrj Space fcuk eryc ds gh Reserved jgrk gSA ,slk djus ij Database dh Size Hkh c< tkrh gS] ftlls Database ij Searching Operations Hkh dkQh le; ysrk gSA ;kuh fdlh ,d Entity esa gh mlds fdlh Multi-Valued eku dks Store djus ds fy, ge mlh Entity dks Use ugha dj ldrs gSaA ;fn ge ,slk djrs gSa] rks ge fofHkUu izdkj dh ubZ leL;kvksa esa Qal tkrs gSaA gkykafd Theoretically ;s lEHko gS fd ge ,d ,slk Database Create dj ldrs gSa] tks fdlh ,d Attribute esa cgqr lkjs Data Store dj ldrk gS] ysfdu Practically bl izdkj ds Database dks Implement djuk dkQh eqf”dy gksrk gSA lkFk gh ;fn fdlh Database ds ,d gh Field esa ,d ls T;knk Data ;k ekuksa dks Store fd;k tkrk gS] rks ml Database esa Searching Operation dsoy Sequential Form esa gh gks ldrk gS] tks fd lcls Slowest Searching Process gksrk gSA tcfd ;fn ,d Field esa dsoy ,d gh Single Value ;k Data dks Store fd;k tkrk gS] rks ge ml Database ij Binary Searching dh Process dks Apply dj ldrs gSa] tks fd ,d cgqr gh Fast Searching Process gksrk gSA ,d lkekU; fu;e ds :i esa ge tc Hkh dHkh fdlh Multi-valued Attribute dks Face dj jgs gksrs gSa] rks og Attribute bl ckr dk ladsr gksrk gS fd gesa Entity esa vkSj u, Fields Created djus iM ldrs gSaA blfy, Same Attribute ds Multiple Values dks Handle djus dk lcls ljy rjhdk ;gh gS fd ge ,d u;k Entity Create djsa vkSj Same Attribute ds mu lHkh Values dks ,d Instance dh rjg ml Entity esa Store djsaA

Identifying Problem Related Entities ftu leL;k ls lEcaf/kr okLrfod Entity dks Identify djuk dbZ ckj dkQh Confusing gksrk gSA ;fn ge gekjs Music Store ds gh mnkgj.k ds vk/kkj ij le>sa] rks D;k ge Music Store dks Entity ds :i esa Identify dj ldrs gSa\ ugha] ge ,slk ugha dj ldrsA D;ksafd Music Store rks mu Entities dk ,d iwjk Collection gS] ftUgsa Music Store Handle djrk gSA Entity rks okLro esa Music Store ds os Items gSa] ftUgsa Database }kjk Manage djuk gSA bl ckr dks Bhd ls le>us ds fy, ge ,d mnkgj.k ysrs gSaA ekuyks fd ge Music Store dks gh ,d Entity ds :i esa Identify dj ysrs gSaA vc bl Entity dks Represent djus ds fy, gesa blds fofHkUu Attributes dk irk djuk gksxk tks fd Music Store ds Items Numbers, Item Titles, Item In Stock, Retail Price vkfn gksaxsA ysfdu pwafd ge iwjs Music Store dks gh ,d Single Entity ds :i esa Describe dj jgs gSa] blfy, gesa blds gj Attribute esa Multiple Values dks Store djuk gksxk vkSj tSlk fd geus igys crk;k fd fdlh Hkh Relational Database esa dksbZ Hkh Attribute Multi-Valued ugha gks ldrk] blfy, ge Music Store dks ,d Single Entity ds :i esa Identify ugha dj ldrs gSa] cfYd gesa bls Entities ds ,d Collection ds :i esa Identify djuk gksrk gSA ,d vkSj mnkgj.k ns[krs gSa] ekuyks fd dksbZ Doctor vius lHkh Patient dh Medical History dks Maintain djrk gSA fdlh Music Store ds Inventory Program dh rjg gh Medical History Hkh ,d rjg dk ,d ls T;knk Entities dk Collection gSA ,d Medical History Appointments o mu Appointments ds nkSjku gksus okyh ?kVukvksa }kjk curk gSA blfy, ;s



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History okLro esa Appointment Entities o Medical Treatment Entities ds Instances dk Collection gS] uk fd Lo;a ,d Entity gSA “History” rks og Output gS ftls ,d Database Application mlds Entities ds Instances (Records) ds Collection ds :i esa Generate djrk gSA

Documenting Logical Data Relationships Entity-Relationship Diagram gesa ,d ,slk rjhdk Provide djrk gS] ftldk iz;kssx djds ge fdlh Entity dks mls Describe djus okys Attributes ds lkFk Logically Represent dj ldrs gSaA ER Diagrams ds dbZ rjhds izpfyr gSa] ysfdu nks rjhdksa dks lcls T;knk Use fd;k tkrk gSA igyk rjhdk Dr. Peter P. S. Chen us Develop fd;k FkkA blfy, bl Data Modeling Diagram dks ER Chen uke fn;k x;k gSA nwljk rjhdk James Martin o Clive Finkelstein us Develop fd;k gS vkSj bls Information Engineering (IE) esa Use fd;k tkrk gSSA ge bu esa ls ftu Hkh rjhds dks Use djds vius Database dk Entity Relationship Data Model Diagram cuk ldrs gSaA nksuksa gh rjhdksa esa ftu Entity dks ,d Rectangle }kjk Represent fd;k tkrk gS vkSj gj Entity dk uke mlds Rectangle ds vUnj fy[kk tkrk gSA mnkgj.k ds fy, ge Customer Entity dks ER Diagram esa fuEukuqlkj Represent dj ldrs gSa%

Customer

Original Chen ds ER Diagram Model esa Entities ds lkFk muds Attributes dks Show djus dh dksbZ lqfo/kk ugha FkhA fQj Hkh yksxksa us Chen ds bl ER Model dks FkksMk lk Modify djds fuEukuqlkj Entity ds Attributes dks Hkh Entity ds lkFk Include dj fy;k gSA Entity ds Identifier Attribute ds uke ds igys ,d Asterisk ( * ) yxkdj Identifier Attribute dks Represent fd;k tkrk gSA Information Engineering Model esa Entity dks mlds Attributes ds lkFk esa fuEukuqlkj fp= }kjk Represent fd;k tkrk gS%

Customer

Customer

FName LName

Telephone *CustID



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*CustID FName LName

Telephone pwafd] Information Engineering Model dks de Space esa T;knk vPNs rjhds ls cuk;k tk ldrk gS] blfy, ge bl iqLrd esa T;knkrj blh Model ds Symbols dks Use djsaxsA gkykafd t:jr gksus ij Chen ds ER Model dks Hkh Use fd;k tk,xkA

Entities and Attributes for Music Store Application gekjs Music Store Database ds Order Entry Form ls gh gesa mu eq[; Entities dk irk py tkrk gS] ftUgsa gesa Music Store Database esa Manage djuk gSA

gkykafd tc ge Database Design Process dks vkxs c<krs gSa] rc Database Design esa vU; Additional Entities dh Hkh t:jr iMrh gSA gekjs Music Store Database ls lEcaf/kr eq[;&eq[; Entities Customer, Order, Distributor, Actor, Producer o Item gSa vkSj bu Entities ls lEcaf/kr os Attributes ftUgsa Database esa Store djuk gSa] mUgsa fuEukuqlkj Information Engineering Diagram }kjk n”kkZ;k x;k gS%



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Domains gj Attribute dk ,d Domain gksrk gS] tks ;s Express djrk gS fd Particular ftu Attribute esa fdl rjg ds eku Store gks ldsaxsA ,d Domain cgqr NksVk Hkh gks ldrk gSA mnkgj.k ds fy, ftu Population ls lEcaf/kr Database esa Male/Female dks Represent djus ds fy, Gender Attribute esa dsoy M/F Character dks gh Store djus dh t:jr gksrh gSA tcfd ftu Customer dk uke Store djus ds fy, Name Attribute esa cgqr lkjs Characters dks Store djuk iMrk gSA ,d Database Management System (DBMS) ,d Domain Constraint ds Through ,d Domain Enforce djrk gSA mlds ckn tc Hkh Database esa dksbZ Data ;k eku Store fd;k tkrk gS] og DBMS Software ml Domain Constraint ds vk/kkj ij ;s r; djrk gS fd Database esa tkus okyk eku mlh Domain dk gS ftlds fy, mls Domain Constraint }kjk Set fd;k x;k gS vFkok ughaA mnkgj.k ds fy, ;fn ftu Customer dh Birth Date dks Store djus ds fy, Database esa DOB Attribute dks Date/Time Domain Constraint ls dks Set fd;k x;k gS] rks DBMS Software ml Attribute esa dsoy mlh Data dks Store djsxk tks Date/Time Format dk gksxkA “ks’k ftu Hkh vU; Domain (Data Type) ds Data dks og DBMS Software Database esa Store ugha djus nsxk ;gka rd fd tc ge Date/Time Domain Constraint dks ftu Attribute ds lkFk Set djrs gSa] rc ge ml Attribute esa 30 February tSlh ftu xyr Date dks Hkh Store ugha dj ldrs gSaA

Documenting Domains ER Diagram dk tks Common Format Use fd;k tkrk gS] mlesa Domain dks Specify djus dh dksbZ lqfo/kk ugha gksrh gS] cfYd ml Diagram ls ,d Document Associated jgrk gS] ftls Data Dictionary dgrs gSaA Data Dictionary ds ckjs esa ge vkxs foLrkj ls i<ssaxsA ge Chen ds ER Model esa gj Attribute ds uhps ml Attribute ds Domain dks Specify dj ldrs gSaA

Practical Domain Choices Music Store ds Entities ds Attributes ds fy, ftu Domains dks Choose fd;k tkrk gS] os Theoretically mu DBMS Softwares ls Independent gksus pkfg,] ftUgsa ge Music Store Database dks Develop djus ds fy, Use djsaxsA fQj Hkh T;knkrj Relational DBMS viuh Query Language ds :i esa SQL dk iz;ksx djrs gSa] ftlesa ftu Attribute dks fuEu Domain Assign fd, tk ldrs gSa%



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CHAR ;s ,d Fixed-Length Domain gksrk gSA bl Domain dks ftu Attribute ds lkFk Associate djus ij ge ml Attribute esa vf/kdre 256 Characters Store dj ldrs gSaA

VARCHAR ;s ,d Variable-Length Domain gksrk gSA bl Domain dks ftu Attribute ds lkFk Associate djus ij ge ml Attribute esa Variable Length ds vf/kdre 256 Characters Store dj ldrs gSaA

INT tc gesa ftu Attribute esa Integer eku Store djuk gksrk gS] rc ge ml Attribute ds lkFk bl Domain dks Associate djrs gSaA

DECIMAL and NUMERIC tc gesa ftu Attribute esa nleyo okys eku dks Store djuk gksrk gS] rc ge ml Attribute ds lkFk bl Domain dks Associate djrs gSaA tc ge ,d Real Number Domain dks ftu Attribute ds lkFk Associated djrs gSa] rc gesa ;s Hkh Specify djuk gksrk gS fd ge nleyo ds ckn ds vadksa lfgr fdrus vadksa rd dk eku Store djuk pkgrs gSa vkSj nleyo ds ckn dqy fdrus vadksa rd dk eku Store djuk pkgrs gSaA mnkgj.k ds fy, Currency Values dks gesa”kk nleyo ds ckn nks la[;kvksa rd Specify djuk gksrk gS] blfy, ;fn ge Currency dks Computer esa Store djus ds fy, ftu Attribute ds lkFk bl Domain dks Associate djuk pkgsa] rks ge DECIMAL (6, 2) Statement }kjk ;s dke dj ldrs gSa] tgka dqy 6 vadksa rd ds Currency eku dks ftu Attribute esa Store fd;k tk ldrk gS tcfd ml eku esa nleyo ds ckn nks la[;kvksa rd dks Store fd;k tk ldrk gSA

DATE tc gesa ftu Attribute esa Date Store djuk gksrk gS] rc ge ml Attribute ds lkFk bl Domain dks Associate djrs gSaA

TIME tc gesa ftu Attribute esa Time Store djuk gksrk gS] rc ge ml Attribute ds lkFk bl Domain dks Associate djrs gSaA

DATETIME tc gesa ftu Attribute esa Date o Time ds Combination dks ,d lkFk Store djuk gksrk gS] rc ge ml Attribute ds lkFk bl Domain dks Associate djrs gSaA



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BOOLEAN tc gesa ftu Attribute esa True ;k False tSlh ftu Logical Value dks Store djuk gksrk gS] rc ge ml Attribute ds lkFk bl Domain dks Associate djrs gSaA

vkt ds u, DBMS Softwares BLOB uke ds ,d u, Data Type dks Hkh Support djrs gSa] ftldk iz;ksx cMs Binary Object tSls fd ftu Graphical Image dks Store djus ds fy, dj ldrs gSaA ftu Attribute ds fy, ,d mfpr Domain dks Choose djus ij Database dh Accuracy dks iwjh rjg ls lqfuf”pr fd;k tk ldrk gSA mnkgj.k ds fy, gekjs ns”k esa Pincode Number 6 Digit dk ,d Number gksrk gSA D;k ,d Pincode Number dks INT Domain ls Associate djuk pkfg,A ugha] ,d Pincode dks nks dkj.kksa dh otg ls INT Domain ls Associate ugha djuk pkfg,A igyk dkj.k ;s gS fd dbZ ns”kksa esa Pincode Numbers ds chp esa Hyphen Symbol dk iz;ksx fd;k tkrk gS vkSj nwljk dkj.k ;s gS fd ;fn Pincode Number dks INT Domain ds lkFk Store fd;k tk,xk] rks dbZ Pincode Number ds igys yxk;k tkus okyk Zero ugha yxk;k tk ldsxk] D;ksafd DBMS ml Preceding Zero dks Remove dj nsxkA lkFk gh Pincode ,d ,slk Number gksrk gS] ftlds lkFk ge dHkh Hkh bl izdkj dh Arithmetical Calculations Perform ugha djrs gSa] blfy, Pincode Number dks Integer ds ctk; Character Form esa Store djus ij gesa bl izdkj dh ijs”kkuh dk lkeuk ugha djuk iMsxkA blh rjg ls tc gesa ftl Data dks lkFk ftl izdkj dh Calculation djus dh t:jr gksrh gS] rc ge ml Data dks Character Form esa Store ugha dj ldrs gSaA mnkgj.k ds fy, ;fn ge ftu Employee dh Salary dks ;fn Character Form esa Store fd;k tk,] rks ge ml Employee dk PF, DA, HRA vkfn Calculate ugha dj ldrs gSa] D;ksafd Character Domain ij ftl izdkj dk Arithmetical Operation Perform ugha fd;k tk ldrkA blh rjg ls ;fn ge ftu Attribute esa Date ;k Time Store djuk pkgsa] rks gesa DATE ;k TIME Domains dks gh Use djuk pkfg,A ;fn ge ftl Date dks Store djus ds fy, Character Format dk iz;ksx djrs gSa] rks ge Date ls lEcaf/kr fofHkUu izdkj dh leL;kvksa esa Qal tk,axsA mnkgj.k ds fy, ekuyks fd ge nks Dates 01/11/2009 o 10/11/2000 dks Character Domain dk iz;ksx djds Database esa Store djrs gSaA vc ;fn ge DBMS ls ;s irk djuk pkgsa fd dkSulh Date igys vkrh gS rks nksuksa gh Dates Character Format esa Store gksus ds dkj.k DBMS bu nksuksa Dates esa ls Alphabetical Order ds vk/kkj ij igys vkus okyh Date dks Calculate djsxk vkSj gesa Result ds :i esa 01/11/2009 iznku djsxk] D;ksafd Alphabetical Order esa 01, 10 ls igys vkrk gS vkSj ge le> ldrs gSa fd ;s ,d xyr Result gSA ;fn ge Character Form esa gh Date dks Store djds ;s tkuuk pkgsa fd dkSulh Date igys vkrh gS] rks gesa bl Date dks YYYY/MM/DD Format esa Database esa Store djuk gksxk vkSj



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bl Format dh Date dks lkjh nqfu;ka esa cgqr gh Rarely Use fd;k tkrk gSA tcfd ;fn ge bu Dates dks Store djus ds fy, DATE Domain dk iz;ksx djrs gSa] rks gesa Date ls lEcaf/kr bl izdkj dh ftu leL;k dk lkeuk ugha djuk iMrk gS] lkFk gh ge DBMS }kjk Date ds fy, Provide dh tkus okyh lqfo/kkvksa dks Hkh izkIr dj ldrs gSaA ;kuh ge nks Dates ds chp Difference dk irk yxk ldrs gSa ;k nks Dates dks vkil esa Compare dj ldrs gSaA

Basic Data Relationships ,d ckj vius Database ls lEcaf/kr lHkh Basic Entities dk irk yx tkus ds ckn gekjk vxyk dke mu Entities ds chp dh vkilh Relationship dks Identify djuk gksrk gSA fdlh Database ds fofHkUu Entities ds chp eq[;r% rhu rjg dh Relationship gks ldrh gSa% One To One Relationship, One To Many Relationship o Many To Many Relationship blls igys fd ge bu Relationships dks le>sa gesa ,d ckr /;ku esa j[kuh gksrh gS fd fdlh Database esa ftruh Hkh Relationships Stored gksrh gSa] os lHkh Relationships Entities ds Instances ds chp gksrh gSaA mnkgj.k ds fy, gekjs Music Store Example ds vk/kkj ij dksbZ Customer mu Items ls Related gksrk gS] ftudk ml Customer us Order fn;k gSA ;kuh Customer Entity dk gj Instance Item Entity ds Order fd, x, Item Instance ls Related gksrk gSA ge ;gka ftl Relationship ds ckjs esa ppkZ dj jgs gSa] og Relationship iwjh rjg ls fdlh Database dk Conceptual Representation gS vkSj bl Relationship dk Data ds Actual Physical Storage ls dksbZ lEca/k ugha gksrk gSA tc ge Data Relationship dks ER Diagram ;k IE Diagram }kjk Document djrs gSa] rc ge fofHkUu Entities ds chp dh Relationship dks Show djrs gSaA bu Diagrams esa ge mu Possible Relationships dks Show djrs gSa tks Database esa Allowable gksrh gSaA ge tc rd fdlh Relationship dks Compulsory :i ls Specify ugha djrs gSa] rc rd ;s t:jh ugha gksrk gS fd Database ls Related gj Entity vkilh Relationship esa Involved gksA mnkgj.k ds fy, Music Store Database fdlh Hkh Customer dh Information dks Database esa Store dj ldrk gS] Hkys gh ml Customer us Music Store dks fdlh Hkh Item ds fy, dksbZ Hkh Order uk fn;k gksA ;gka ;s t:jh ugha gS fd ogh Customer Music Store Database esa Store gks ldrk gS] ftlus dksbZ Music Store dks fdlh Title ds fy, dksbZ Order fn;k gksA

One To One Relationships ekuyks fd fdlh NksVs ls “kgj esa dsoy ,d gh Airport gS vkSj fdlh Database esa og “kgj o Airport nksuksa gh ,d Entity ds :i esa Involved gSaA bl fLFkfr esa City o Airport nksuksa gh ml Database esa nks vyx Entities ds Instance ds :i esa Represent gksaxsA vr% City o Airport ds chp One To One dh Relationship dks bl rjg ls Express fd;k tk ldrk gS fd Airport dsoy ,d City esa gh Situated gS vkSj ml City esa dsoy ,d gh Airport gSA



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;s mnkgj.k One To One Relationship dk ,d vkn”kZ mnkgj.k gS] D;ksafd bl Database esa fdlh Hkh le; ,d City ls dsoy ,d gh Airport Related gksxk vkSj ml ,d Airport ls dsoy ,d gh City Related gksxhA gkykafd fdlh “kgj esa ,d ls T;knk Airports gks ldrs gSa] ysfdu ge ;gka ,d cgqr gh NksVs “kgj ds Airport Database dks Manage dj jgs gSa vkSj ge ;s eku jgs gSa fd fdlh Hkh NksVs “kgj esa ,d ls T;knk Airport ugha gks ldrs gSaA ;fn gekjs ikl nks Entities A o B ds nks Instances Ai o Bi gksa] rks bu nksuksa Entities ds Instances ds chp One To One dh Relationship dsoy rHkh lEHko gS] tc fdlh Hkh le; Ai Entity B ds Zero ;k One Instance ls Related gks vkSj Bi Entity A ds Zero ;k One Instance ls Related gksA fdlh Hkh Business Database Application esa One To One dh Relationship cgqr gh Rare Case esa curh gSA mnkgj.k ds fy, ekuyks fd gekjk Music Store ,d u, Distributor ls Dealing djuk r; djrk gSA Music Store ml u, Distributor dks dsoy ,d gh Special Title dk Order nsrk gSA vc ;fn ge ml u, Distributor dks vius Database esa LFkku nsa] rks ge ns[krs gSa fd ml u, Distributor Entity dk Instance Music Store ds Item Entity ds dsoy ,d Instance ls Related gksrk gSA blfy, ;gka ij ml u, Distributor o Item ds chp One To One dh Relationship curh gSA vc ;fn Music Store ml u, Distributor dks dbZ vkSj Titles ds Order nsrk gS] rks ;gka ;s fu;e Violate gks tkrk gS fd og u;k Distributor Music Store ds dsoy ,d gh Item ls Related gSA bl fLFkfr esa ml u, Distributor Entity ds Instance o Item Entity ds Instance ds chp One To One ds LFkku ij One To Many dh Relationship cu tkrh gSA D;ksafd vc og u;k Distributor Music Store ds ,d ls T;knk Items ds Titles ls Related gks tkrk gSA blh rjg ls ;fn ge Music Store Database esa Credit Card uke dk ,d vkSj Entity Create djrs gSa] ftlesa mu Credit Cards ds Data dks Hold fd;k tkrk gS] ftudk iz;ksx os Customer viuh m/kkjh pqdkus ds fy, djrs gSa] ftudk dqN iSlk Music Store esa cdk;k gSA pwafd gj Customer dsoy ,d gh Credit Card ls viuk iSlk pqdkrk gS] blfy, ;gka ij Hkh Customer Entity ds Instance o Credit Card Entity ds Instance ds chp One To One dh Relationship Create gksrh gSA Credit Card Entity ds fy, Credit Card dk Number, Type o Expiration Date Attributes gks ldrs gSaA ;fn ge ;s eku ysa fd gj Customer ds ikl dsoy ,d gh Credit Card gksrk gS] rks pwafd Credit Card ds fdlh Hkh Attribute dk eku Multi-Valued uk gksus dh otg ls gesa Credit Card dks ,d vyx Entity ds :i esa Represent djus dh t:jr ugha gSA ge Credit Card ds fofHkUu Attributes dks Customer dh Information ds lkFk Store dj ldrs gSaA ge tc Hkh dHkh fdlh Database ds lUnHkZ esa One To One Relationship dks Identify djrs gSa] rks gesa /;ku ls ;s ns[k ysuk pkfg,] fd dgha ge One To Many dh Relationship dks rks One To One dh Relationship ugha eku jgs gSa ;k dgha ,d gh Entity dks rks nks Entity ds :i esa Represent djus dh dksf”k”k rks ugha dj jgs gSaA



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One To Many Relationships fdlh Database ds fofHkUu Entities ds chp dh ;s ,d cgqr gh Common Relationship gksrh gSA okLro esa Maximum Database esa ftruh Hkh Relationships gksrh gSa] muesa ls T;knkrj One To Many dh gh Relationship gksrh gSaA One To One dh Relationship rks Rare Case esa gh curh gSA Music Store Database ds lUnHkZ esa Hkh Database ds fofHkUu Entities ds Instances ds chp ;s gh Relationship Define gks jgh gSA mnkgj.k ds fy, Music Store cgqr lkjs Titles ds fy, Distributors dks Order ns ldrk gS vkSj Music Store ,d Title dk Item dsoy ,d gh Distributors ls izkIr djrk gSA blh rjg ls ,d Customer Music Store ij dbZ Orders Place dj ldrk gS ysfdu ,d Order dsoy ,d gh Customer nsrk gSA tSls Order Number 001 fdlh Rahul uke ds Customer us fn;k gks] rks blh Number dk dksbZ nwljk Order fdlh nwljs Customer }kjk Music Store dks ugha fn;k tk ldrk gSA ;fn gekjs ikl nks Entities A o B ds nks Instances Ai o Bi gksa] rks bu nksuksa Entities ds Instances ds chp One To Many dh Relationship dsoy rHkh lEHko gS] tc fdlh Hkh le; Ai Entity B ds Zero, One ;k More Instances ls Related gks vkSj Bi Entity A ds Zero ;k One Instance ls Related gksA One To Many dh Relationship dks ,d Family Relationship ds :i esa vkn”kZ rjhds ls Represent fd;k tk ldrk gSA ,d eka o mlds cPapksa ds chp One To Many dh Relationship gksrh gS] ftlesa ,d eka ds dbZ cPps rks gks ldrs gSa] ysfdu fdlh Hkh cPps dh dsoy ,d gh eka gks ldrh gSA Bhd blh rjg ls ;fn ge ,d vkSj mnkgj.k ns[ksa rks ,d Computer o mlds CPU ds chp Hkh One To Many dh Relationship dks Represent fd;k tk ldrk gS] tgka ,d CPU dks dsoy ,d gh Computer esa Install fd;k tk ldrk] tcfd ,d Computer esa ,d ls T;knk CPU dks Install fd;k tk ldrk gSA ;fn blh Concept dks ge Music Store ds Database ij Apply djsa] rks ge dg ldrs gSa fd Music Store o mlds Distributor ds chp One To Many dh Relationship gksrh gS] tgka Music Store ,d Title ds fy, fdlh ,d gh Distributor dks Order ns ldrk gS] tcfd ogh Title Music Store dks ,d ls T;knk Distributor iznku dj ldrs gSaA ,d ckr /;ku j[ksa fd tc ge Data Relationships dks Specify dj jgs gksrs gSa] rc ge lHkh lEHko Relationships dks Indicate dj jgs gksrs gSa vkSj ;s t:jh ugha gksrk gS fd lHkh Entities ds lHkh Instances gj Documented Relationship esa Hkkx ysaA ;kuh gekjs Music Store Database ds vk/kkj ij ;s t:jh ugha gS fd dksbZ Distributor Instance fdlh Item Entity ds Zero, ,d ;k ,d ls T;knk Instances ls Related gksA

Many To Many Relationships ;s Relationships Hkh dkQh Common Relationships gSaA ;fn ge Music Store Database ds lUnHkZ esa bl Relationship dks ifjHkkf’kr djsa] rks Customer Entity o Item Entity ds chp Many To Many dh Relationship gksrh gSA D;ksafd ,d Customer ,d ls T;knk Titles dk Order ns ldrk gS vkSj ,d gh Title ds fy, ,d ls T;knk Customer Order ns ldrs gSaA



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blh rjg ls ,d Distributor o ,d Item ds chp Hkh Many To Many dh Relationship gks ldrh gS] ftlesa ,d gh Distributor dks ,d ls T;knk Title ds fy, Order fn;k tk ldrk gS vkSj ,d gh Title dks ,d ls T;knk Orders esa Place fd;k tk ldrk gSA ;fn gekjs ikl nks Entities A o B ds nks Instances Ai o Bi gksa] rks bu nksuksa Entities ds Instances ds chp Many To Many dh Relationship dsoy rHkh lEHko gS] tc fdlh Hkh le; Ai Entity B ds Zero, One ;k More Instances ls Related vkSj Bi Entity A ds Zero, One ;k More Instances ls Related. Many To Many Relationship Database Design esa nks cMh leL;k,a iSnk djrk gS] ftUgsa vkxs foLrkj ls le>k;k x;k gSA

Weak Entities and Mandatory Relationships geus fofHkUu Relationships dks Discuss djrs le; Relationship dks “Zero” Instance ls Hkh Related crk;k gS] tks bl ckr dks Indicate djrk gS fd vkilh Relationship esa Specify fd, x, Entities ds fdlh Instances dk Relationship esa Participate djuk Optional gSA mnkgj.k ds fy, ;fn ge Music Store Database ds lUnHkZ esa bl ckr dks le>sa] rks ,d Customer dh Information dks ml le; Hkh Database esa Store fd;k tk ldrk gS] tcfd mlus fdlh Item ds fy, dksbZ Order ugha fd;k gksrk gSA bl fLFkfr esa ,d Customer Entity dk dksbZ Instance Item Entity ds fdlh Hkh Instance ls Related ugha gksrk gS ;k nwljs “kCnksa esa dgsa rks ,d Customer Entity dk dksbZ Instance Item Entity ds Zero Instance ls Related gksrk gSA gkykafd ,d Customer tc dksbZ Order Place ugha djrk gS] rc Hkh ml Customer dh Database esa Entry dh tk ldrh gS] ysfdu ;fn ge bl Concept dks Reverse Order esa ysa] rks ,slk lEHko ugha gks ldrkA ;kuh gj Order dk fdlh ,d Customer ls Related gksuk t:jh gksrk gSA fcuk fdlh Customer ds Order fn, gq,] Music Store Database esa ,d Order Place gh ugha gks ldrk] D;ksafd fdlh Hkh Order dks Place djus ds fy, ,d Customer t:j gksuk pkfg,A ;fn ge bl Discussion ds vk/kkj ij le>sa rks ;gka Order ,d Weak Entity gS] D;ksafd ;s ,d ,slk Entity gS] ftls Database esa rc rd Store ugha fd;k tk ldrk gS] tc rd fd ml Order Instance ls Related dksbZ nwljk Entity Instance ml Database esa Present uk gks vkSj ml Order ls Related uk gksA Customer Entity dk ,d Instance Zero, One ;k More Orders ls Related gks ldrk gSA fQj Hkh ,d Order dk dsoy ,d vkSj flQZ ,d gh Customer Entity Instance ls Related gksuk t:jh gksrk gSA Weak Entity ds fy, Zero Option Available ugha gksrk gSA bl fLFkfr esa Customer o Order ds chp dh Relationship ,d t:jh ;kuh Mandatory ;k Compulsory Relationship gS] ftls Database dks Bhd ls Manage djus ds fy, Database esa ifjHkkf’kr djuk t:jh gksrk gSA fdlh Database dh Consistency o Integrity dks Maintain djus ds fy, mlds lHkh Weak Entities o ml Weak Entity ls Associated Mandatory Relationship Entity dks Identify djuk dkQh egRoiw.kZ gksrk gSA



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budk Database ij vkilh izHkko tkuus ds fy, ekuyks fd ge ,d ,slk Order Database esa Store djrs gSa] ftlls Belonged Customer dk irk ugha gSaA bl fLFkfr esa ge ml Order esa Specify fd, x, Items dks dHkh Hkh fdlh Customer rd Ship ugha dj ldrs gSa] D;ksafd ml Order esa ml Customer dh tkudkjh gh ugha gksrh gS] ftls ml Order ds Items Ship djus gSaA blh Concept ds vuqlkj ge Order o Order Lines ds chp dh Relationship dks Hkh One To Many ds Relationship ds :i esa Define djrs gSa] D;ksafd ge ugha pkgrs gSa fd fcuk fdlh Order ls Related gq, dksbZ Order Line Database esa Store gksA Order Line fdlh Order ij fLFkr fdlh Specific Item dks Refer djrk gSA ;kuh ,d Order Line rc rd Meaningless gksrk gS] tc rd fd ge ;s ugha tkurs gSa fd og Order Line fdl Order ls Belong djrk gSA blds ctk; ge Music Store ij miyC/k fdlh Hkh Item dks Database esa Store dj ldrs gSa] tcfd gesa ;s tkuus dh t:jr ugha gksrh gS fd ml Item dks fdl Supplier us Hkstk gS] tcfd ge ;gka ij ;s eku jgs gSa fd gj Item fdlh ,d Supplier ls vkrk gSA bl fLFkfr esa Supplier o Item ds chp okLro esa Zero To Many dh Relationship gks tkrh gSA

Documenting Relationships Chen o IE nksuksa gh rjhdksa ds ER Diagrams esa Relationship dks vyx rjhdksa ls Represent fd;k tkrk gSA nksuks gh rjhdksa ds vius Qk;ns o dfe;ka gSaA Chen Method esa Relationship dks Represent djus ds fy, Diamond Symbol dk iz;ksx fd;k tkrk gS vkSj Entities ds chp Relationship ds Type dks Represent djus ds fy, Arrow Based Lines dk iz;ksx fd;k tkrk gSA mnkgj.k ds fy, fuEu ER Diagram dks nsf[k,%

bl Diagram esa ge Customers o Orders ds chp dh Relationship dks ns[k ldrs gSaA Customer dh rjQ tks Single Arrow Point dj jgk gS og Arrow Indicate djrk gS fd ,d Order dsoy ,d gh Customer ls Belong dj jgk gSA tcfd Orders Entity dh rjQ dk Double Arrow bl ckr dks Indicate djrk gS fd ,d Customer ,d ls T;knk Orders Place dj ldrk gSA Diamond ds chp fy[kk x;k “kCn Relationship ds lEca/k esa dqN tkudkjh iznku djrk gSA Chen Model esa nks Alternative Styles gSaA igys Style esa Arrows dks Numbers o Letters ls Replace dj fn;k tkrk gSA Number “1” ;s Indication nsrk gS fd ,d Order fdlh ,d Customer ls vkrk gSA tcfd “M” ;k “N” Character ;s Indication nsrk gS fd Customer ,d ls T;knk Orders Place dj ldrk gSA bl rjhds dks Apply djus ij gesa fuEukuqlkj Diagram izkIr gksrk gS%



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nwljk Alternative ml Problem dk Solution n”kkZrk gS] tks rc iSnk gksrh gS tc ge Relationship dks nksuksa Directions esa Read djrs gSaA ;kuh “Customer Places Order” rks ,d Meaningful Information gSA ysfdu “Order Places Customer” fdlh rjg dh dksbZ Meaningful Information iznku ugha djrk gSA bl leL;k dks Solve djus ds fy, ER Diagram esa Diamond ls Relationship Represent djus okys Arrows o Relationship ds uke dks Remove dj fn;k tkrk gS vkSj Diagram dks fuEukuqlkj Inverse dj fy;k tkrk gS%

vc ;s Diagram T;knk Meaningful Information Provide djrk gS] tks fuEukuqlkj gS fd %

1 1 Customer M Orders Place dj ldrk gSA ;kuh “1 Customer Places Many Orders” vkSj 2 1 Order dsoy 1 Customer gh Place dj ldrk gSA ;kuh “1 Order is Placed by 1 Customer”

Chen ds Model esa ,d cgqr gh cMh Limitation gS vkSj oks gS ER Diagram dks Draw djus dhA Chen ds ER Diagram esa fdlh Weak Entity o Mandatory Relationship dks Represent djus dk dksbZ Li’V rjhdk ugha gSA mnkgj.k ds fy, Music Store Database ds fy, Order ,d Weak Entity gS vkSj fcuk fdlh Customer ds ;s Entity Database esa Store ugha fd;k tk ldrk vkSj Customer Entity ds lkFk bldh Relationship t:jh ;kuh Mandatory gSA dqN Database Designers us Chen Method esa ,d u;k Symbol Add fd;k gS ftlesa fdlh Weak Entity dks fuEukuqlkj ,d Double Bordered Rectangle }kjk n”kkZ;k tkrk gS% tc Hkh dHkh fdlh ER Diagram esa fdlh Weak Entity dks Represent fd;k tkrk gS] rc ;s Symbol bl ckr dks Indicate djrk gS fd ;s Entity o blds ,d Parent Entity nksuksa ds chp esa Mandatory Relationship gSA ysfdu ;fn bl Entity ds lkFk ,d ls T;knk Parent Entities Related gksa] rks bl ckr dks lkekU; rjhds ls r; djuk eqf”dy gks tkrk gS fd dkSuls Entity ds lkFk bl Weak Entity dh Relationship Mandatory gSA Chen Method ds vykok ge Information Engineering Method dks Use djds Hkh ER Relationship Model dks Create dj ldrs gSaA IE Method esa Line ds End ds vk/kkj ij gh fofHkUu izdkj dh Relationships dks Represent fd;k tkrk gS] tks fd Chen ds Method dh rqyuk esa ER Diagram dks T;knk ljy cuk nsrk gSA mnkgj.k ds fy, fuEu fp= esa mlh One To Many Relationship dks n”kkZ;k x;k gS] ftls geus Chen ds Method }kjk n”kkZ;k gSA bl fp= esa Line ds End ds vk/kkj ij ge bl ckr dk irk

Order



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yxk ldrs gSa fd dkSulh Relationship Mandatory gS vkSj dkSulk Entity ,d Weak Entity gSA

Customer Entity ds vkxs tks nks [kMh Lines (||) gSa] mudk eryc ;s gksrk gS fd gj Order flQZ vkSj flQZ ,d Customer ls Related gSA pwafd 0 Optional ugha gS] blfy, bu Entities ds chp dh Relationship Mandatory gSA blh rjg ls Order Entity ds lkFk Connect fd, x, 0 o rhu Legs dk eryc ;s gS fd ,d Customer Zero, One ;k More Orders ls Related gks ldrk gSA ,d IE Diagram esa Line ds vUr esa eq[;r% pkj Symbols dks Use fd;k tk ldrk gS%

1 || : One and Only One (Mandatory Relationship) 2 0| : Zero or One 3 >| : One or More (Mandatory Relationship) 4 >0 : Zero, One or More

vc ;fn ge Music Store Database ds fofHkUu Entities ds chp dh Relationships dks IE Diagram }kjk Represent djsa] rks cuus okyk Diagram fuEukuqlkj cusxk%



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bl IE Diagram }kjk fuEu Relationships Model gks jgs gSa%

1 ,d Customer Zero, One ;k More Orders Place dj ldrk gS tcfd ,d Order ,d vkSj flQZ ,d Customer }kjk Place fd;k tk ldrk gSA

2 ,d Order esa ,d ;k ,d ls T;knk Items gks ldrs gSa tcfd ,d Item Zero, One ;k

More Orders esa Appear gks ldrk gSA

3 ,d Actor Zero, One ;k More Items esa Appear gks ldrk gS vkSj blh rjg ls ,d Item esa Zero, One ;k More Actors gks ldrs gSaA ( dbZ ckj ,slh Films Hkh curh gSa] ftuesa Human Actors ds LFkku ij Animal Actors gksrs gSaA blfy, gesa”kk ;s t:jh ugha gksrk gS fd gj Item de ls de ,d Actor ls Related gksA )

4 gj Item ds Zero, One ;k More Producers gks ldrs gSa vkSj gj Producer Zero,

One ;k More Items ds fy, Responsible gksrk gSA gkykafd ge Practically rc rd fdlh Producer dks Database esa Store ugha djrs gSa] tc rd fd og Producer fdlh Item ls Related uk gksA Producer o Items ds chp dh Relationship dks Optional Means ds :i esa Specify djds ge fcuk Item dh Information Store fd, gq, Hkh Producer dh Information dks Database esa Store dj ldrs gSaA

bl Design esa Notice djus okyh tks lcls cMh pht gS oks ;s gS fd bl Design esa rhu Many To Many Relationships gSa] tks fd Order To Item, Actor To Item o Producer To Item ds Entity ds chp gSA blls igys fd ge bl Data Model dks fdlh Relational Database ij Map djsa] bUgsa fdlh vU; rjhds ls Handle djuk gksxk] D;ksafd fdlh Hkh Relational Database esa ge Many To Many Relationship dks Directly Map ugha dj ldrs gSaA

Dealing with Many To Many Relationships tSlkfd geus igys crk;k gS fd Many To Many Relationship ds lkFk dqN vyx izdkj dh leL;k,a gSaA lcls igyh leL;k rks ;gh gS fd dksbZ Hkh Relational Data Model Many To Many Relationship dks Directly Handle ugha dj ldrk gSA fdlh Relational Data Model esa ge dsoy One To One ;k One To Many Relationship dks gh Handle dj ldrs gSaA bldk eryc ;s gqvk fd geus Music Store Database esa ftl Many To Many Relationship dks Identify fd;k gS] mUgsa One To Many Relationships ds Collections ds :i esa Convert djds Relational Data Model esa Use djuk gksxk] rkfd ge bUgsa ,d Relational DBMS esa Use dj ldsaA nwljh leL;k FkksMh T;knk tfVy gSA bls le>us ds fy, ekuyks fd Music Store fdlh Distributor dks dksbZ Order nsrk gS vkSj Music Store ij dksbZ Customer Order Place djrk gSA blfy, Order o Item ds chp Many To Many dh Relationship curh gS] D;ksafd gj Order esa ,d ls T;knk Items Appear gks ldrs gSa vkSj ckn esa gj Item dbZ Orders ij Appear gks ldrk gSA tc dHkh Music Store fdlh Item ds fy, dksbZ Order Place djrk gS] rc Item ds Copies dh la[;k Music Store dks izkIr gksus okyh Copies dh la[;k ls fHkUu gks ldrh gSA ;kuh gks ldrk gS fd Music Store fdlh Item ds pkj Copy izkIr djuk pkgrk gks tcfd Stock dh deh ds dkj.k mls og Item dsoy rhu gh izkIr gksA



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vc loky ;s gS fd Order fd, x, Item dh Quantity dks dgka Store djuk pkfg,\ D;ksafd ;s Quantity Order Entity dk fgLlk (Attribute) rks gks ugha ldrk D;ksafd Quantity ml Item ij Depend djrh gS] ftls Music Store Order dj jgk gSA blh rjg ls ;s Quantity Item Entity dk Hkh fgLlk (Attribute) ugha gks ldrk D;ksafd Quantity fdlh Specific Order ij Depend djrk gSA bl izdkj ds Attribute esa Store gksus okys Data dks Relationship Data dgk tkrk gS] tgka dksbZ Data fdUgha Entities ds Relationship dk fgLlk gksrk gS uk fd og Data Relationship esa Hkkx ysus okys fdlh Entity dk fgLlk (Attribute) gksrk gSA pwafd fdlh Relationship esa Attributes ugha gksrs gSaA blfy, gesa Relationship Data dks Represent djus ds fy, fdlh ,sls Entity dh t:jr gksrh gS] tks nks Entities ds chp dh Relationship dks Represent djs vkSj bl Entity esa ge ml Relationship Data dks ,d Attribute ds :i esa Store dj ldrs gSaA ;kuh tc fdUgh nks Entities ds chp dksbZ ,slk Data gks tks fdlh Hkh Entity esa Lora= :i ls Represent ugha gks ldrk] ysfdu nksuksa Related Entities ds Group ij vk/kkfjr gksrk gS] rc gesa bl izdkj ds Relationship Data dks Store djus ds fy, ,d u, Entity dh t:jr iMrh gS vkSj bl izdkj ds Data dks ml u, Entity esa Store fd;k tkrk gSA

Composite Entities os Entities, tks nks vU; Entities ds chp dh Relationship dks Represent djus ds fy, Describe fd, tkrs gSa] Composite Entities dgykrs gSaA Composite Entities fdl izdkj ls dke djrs gSa] bl ckr dks ge ,d mnkgj.k }kjk le>us dh dksf”k”k djrs gSaA ge le> ldrs gSa fd Music Store ds Customers ds Orders o Music Store ds Items ds chp Many To Many dh Relationship gS D;ksafd ,d Order esa dbZ Items Appear gks ldrs gSa vkSj leku Item dks ,d ls T;knk Order esa Appear fd;k tk ldrk gSA vc gesa ,d ,sls Entity dh t:jr gksrh gS] tks gesa ;s crk, fd ,d Specific Title fdlh Specific Order ij Appear gks jgk gSA bl Concept dks fuEu fp= }kjk le>k;k tk jgk gS%



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bl fp= esa rhu Order Instances gSa vkSj rhu gh Item Instances gSaA igyk Order (Order #1) Customer Number #0985 us fn;k gS vkSj bl Order esa mlus dsoy ,d gh Item ( item #09244) dk Order fn;k gSA nwljs Order (Order #2) Customer #0985 us fn;k gS vkSj bl Order esa mlus ftu nks Items dk mYys[k fd;k gS] mudk Number #02944 o #10101 gSA ;kuh nwljs Order esa Item Number #02944 rks fQj ls Appear gks gh jgk gS lkFk gh Item Number #10101 Hkh Appear gks jgk gSA rhljk Order tks fd Order #3 gS] og Customer Number #1212 us Place fd;k gS vkSj blesa Hkh nks Items Item Number #10101 o Item Number #00250 dk Order fn;k x;k gSA bl fp= esa ge ns[k ldrs gSa fd rhu Customers us rhu Orders Place fd, gSa vkSj rhuksa Orders esa dqy ikap Items dks Order fd;k x;k gSA bldk eryc ;s gS fd ;fn rhuksa Orders dks iwjs fd, tk,a] rks Item Number #02944 dh nks Copies, Item Number #10101 dh nks Copies o Item Number #00250 dh dsoy ,d Copy ;kuh dqy ikap Copies Sell gksaxhA bl Diagram ds chp dk fgLlk gh og Composite Entity gS] tks fd gj Order dks fdlh ,d Specific Item ls Connect dj jgk gSA gekjs bl Example Diagram esa dqy ikap Instances gSa] ftUgsa ge “Line Items” dgsaxsA ;s Line Item Entities, Order o Item ds chp dh Relationship dks Represent djus ds fy, Create fd, x, gSaA bl Diagram esa ge ns[k ldrs gSa fd gj Order izR;sd Item ds fy, dsoy ,d Line Item Instance ls Related gSA nwljs rjhds ls ns[ksa rks izR;sd Item gj Order ij Appear gksus ds fy, fdlh ,d Line Item Instance ls Related gSA bl Diagram ds vk/kkj ij izR;sd Line Item Instance ,d vkSj flQZ ,d Order ls Related gS lkFk gh ogh Line Item ,d vkSj flQZ ,d Item ls Related gSA ifj.kkeLo:i ,d Order o mlds Line Items ds chp One To Many dh Relationship gS] D;ksafd ,d Order



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dbZ Line Items ls Related gS vkSj Item og Order, ftl ij og Item Appeared gS] ds chp One To Many dh Relationship gS D;ksafd ,d Item ,d ls T;knk Line Items ij Appear gSA bl rjg ls bl Diagram esa ge ns[k ldrs gSa fd ,d Composite Entity dh mifLFkfr ls Original Many To Many dh Relationship nks One To Many dh Relationship esa Convert gks jgh gSA ;fn gekjs Database ls lEcaf/kr dksbZ Relationship Data gS] rks ml Data dks Store djus ds fy, ge bl Composite Entity esa gh ml Data ds fy, Appropriate Attribute Create dj ldrs gSaA mnkgj.k ds fy, Order fd, x, Item dh Quantity dks Store djus ds fy, bl Composite Entity esa Quantity uke dk Field ;k Attribute Create dj ldrs gSaA blds lkFk gh ge bl Composite Entity esa bl ckr dh tkudkjh j[kus ds fy, ,d Flag Attribute Create dj ldrs gSa] tks bl ckr dh tkudkjh ns fd Order fd, x, Items dks Ship fd;k tk pqdk gS ;k ugha vkSj ;fn Ship fd;k tk pqdk gS] rks Shipping Date dks Store djus ds fy, Shipping Date Attribute dks Hkh blh Composite Entity esa ,d Field ds :i esa Specify fd;k tk ldrk gSA Chen ds ER Method esa Composite Entity dks ER Diagram esa Draw djus ds fy, fuEukuqlkj Symbol dk iz;ksx fd;k tkrk gS] tcfd Information Engineering Method esa Composite Entity dks ER Diagram esa Represent djus dk dksbZ rjhdk ugha gSA

Music Store Database ds lHkh Many To Many Relationships dks Eliminate djus ds fy, gesa gj Many To Many Relationship dks ,d Composite Entity }kjk nks One To Many Relationships esa Convert djuk gksxkA tSlkfd ge gekjs Music Store Database ds fiNys IE ER Diagram esa ns[k ldrs gSa] mlesa rhu Many To Many Relationships gSa] blfy, bu rhuksa Many To Many Relationships dks Remove djus ds fy, gesa rhu Composite Entities dks fuEukuqlkj Create djuk gksxk%

1 Order Lines Order Lines Entity ,d Item dks ,d Order ij Represent djrk gSA gj Order dh dbZ “Order Lines” gks ldrh gSa tks fd vyx&vyx Items ls Connect gksa] ysfdu Order Line ,d vkSj flQZ ,d Order ij Appear gks ldrk gSA blh rjg ls ,d Order Line esa ,d vkSj flQZ ,d Item Appear gks ldrk gS ysfdu ,d gh Item ,d ls T;knk Order Lines esa Appear gks ldrk gS vkSj izR;sd Item fdlh Different Order ls Connected gksrk gS D;ksafd ,d gh Item ds fy, ,d ls T;knk Orders Place fd, tk ldrs gSaA

2 Performance Performance Entity ;s Represent djrk gS fd ,d Actor ,d Film esa Appear gksrk gSA gj Performance ,d vkSj flQZ ,d Film ds fy, gksrh gS] tcfd ,d Film esa ,d ls T;knk Performance gks ldrh gSa] D;ksafd ,d Film esa ,d ls T;knk Actor gks ldrs gSaA blh rjg ls ,d Actor izR;sd Film esa ,d Performance ls Related



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gksrk gS] ysfdu ,d Film esa dsoy ,d vkSj flQZ ,d Performance ls Related gksrk gSA

3 Production

Production Entity ;s Represent djrk gS fd ,d Producer ,d Film ij dke djrk gSA ,d Producer dbZ Productions esa Involved gks ldrk gS tcfd gj Production dsoy ,d vkSj flQZ ,d Producer ls Related gksrk gSA Item ds lkFk dh Relationship ;s Indicate djrk gS fd gj Film dks ,d ls T;knk Producers Produce dj ldrs gSa ysfdu izR;sd Production fdlh ,d Item ls Related gksrk gSA

pwafd Composite Entities dks eq[;r% nks Entities ds chp dh Relationships dks Indicate djus ds fy, Create fd;k tkrk gS] blfy, Composite Entity dk mlds nksuksa Child Entities ls Related gksuk t:jh gksrk gSA ,slk blfy, gksrk gS D;ksafd gj Child Entity dk mlds Parent Entity ls Related gksuk Compulsory ;k Mandatory gksrk gSA vc cuk;k tkus okyk Modified IE Design fuEukuqlkj gksxk%



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Relationships and Business Rules Database Design dbZ rjhdksa ls Science ds lkFk&lkFk ,d Art Hkh gSA fdlh Business ds fy, fdlh Database dk dkSulk Design iwjh rjg ls Correct gksxk] ;s ml Organization ds Business Rules ij fuHkZj gksrk gSA vyx&vyx Organizations vius vyx&vyx Business Rules ds vk/kkj ij dke djrs gSa] blfy, ,d Organization ds fy, Design fd;k x;k Database dHkh Hkh iwjh rjg ls fdlh nwljs Organization ds Database ij iwjh rjg ls Apply ugha fd;k tk ldrk gSSA mnkgj.k ds fy, ekuyks fd ge fdlh Retail Establishment ds fy, ,d Database Create djuk pkgrs gSa] ftlds cgqr lkjs vU; Stores gSaA bl Database esa tks eq[; ckr Handle dh tk,xh] og mu Employees dk Schedule gksxk] tks ml Retail Establishment ds fofHkUu Stores ij dke djrs gSaA blls igys fd ge ,slk Database Design djsa] gesa Employee o Store ds chp dh Relationship dks Identify djuk gksxkA Employee o Store ds chp dkSulh Relationship gksxh\ One To One dh ;k One To Many dhA D;ksafd Retail Establishment dk Chairman dHkh Hkh fdlh Hkh Employee dks vius fdlh Hkh Store ij Hkst ldrk gSA ,slk t:jh ugha gS fd tks Employee ftl Store ds fy, fu;qDr fd;k tk,xk] og gesa”kk mlh Store ij fu;qDr jgsxkA gj Employee gesa”kk ,d gh Store ds fy, fu;qDr fd;k tkrk gS] rks Employee o Store ds chp One To Many dh Relationship Identify gksrh gS vkSj ;fn gj Employee izR;sd Store ij FkksMk&FkksMk le; O;rhr djrk gS] rks Employee o Store ds chp Many To Many dh Relationship Identify gksrk gSA bl fLFkfr esa ekeyk ;s ugha gksrk gS fd dkSulk Design lgh gS vkSj dkSulk xyr cfYd bl fLFkfr esa dkSulk Design lgh gS] ;s ckr ml Organization ds dke djus ds rjhds ij fuHkZj djrk gS] fd og Organization vius Business dks fdl rjg ls Operate djrk gSA ;kuh bl ckr ls dksbZ QdZ ugha iMrk gS fd ge Database Design ds lEca/k esa fdruk T;knk tkurs gSa] cfYd ge rc rd ,d vPNk Database Create ugha dj ldrs gSa] tc rd gekjk Database fdlh Business Environment dh fofHkUu Relationships dks Accurate rjhds ls Reflect ugha djrk gSA

Data Modeling and Data Flow Data Model Design djrs le; tks lcls T;knk Common Mistakes dh tkrh gSa] oks Data Model o Data Flows ds chp Confusion dh Mistake gksrh gSaA Data Flow bl ckr dks Show djrk gS fd fdlh Organization esa Data dks fdl izdkj ls Handle fd;k tkrk gS] Data dks dgka Store fd;k tkrk gS vkSj Data ds lkFk D;k Processing dh tkrh gSA tcfd Data Medal Data dh Internal ckrksa dks rFkk Data ds chp dh vkilh Relationships dks fcuk bl ckr dh ijokg fd, Represent djus dk dke djrk gS] fd Data dks dkSu Handle dj jgk gS vkSj Data ds lkFk fdl izdkj dh Processing dks Apply fd;k tk jgk gSA



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Data Flows dks lkekU;r;k Data Flow Diagrams(DFD) esa Document fd;k tkrk gSA mnkgj.k ds fy, vxys fp= esa ge Music Store Organization ds Top Level Data Flow Diagram dks ns[k ldrs gSaA

bl fp= dk Sequence mu yksxksa dks iznf”kZr dj jgk gS fd tks Data dks Handle dj jgs gSaA bl fp= ds Circles mu Processes dks Represent dj jgs gSa] ftUgsa Data ij Apply fd;k tkrk gSA ftl txg ij Data dks Store fd;k tkrk gS] mls nks Parallel Lines ds :i esa n”kkZ;k x;k gSA gekjs bl mnkgj.k esa eq[; Storage dks “Main Database” “kCn ls Represent fd;k x;k gSA bl fp= esa n”kkZ, x, Arrows bl ckr dks Indicate djrs gSa fd Data fdlh LFkku ls fdl LFkku dh rjg Flow ;k Pass fd, tk jgs gSaA Data Flow Diagrams dk iz;ksx lkekU;r;k Design fd, tk jgs System dh vkSj vf/kd Details Provide djus ds fy, fd;k tkrk gSA fiNys fp= ds Order ysus dh izfØ;k dks vxys fp= esa FkksMk lk vkSj Modify djds “Take Order” dh Process dks Represent fd;k x;k gSA



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bl fp= esa ge ns[k ldrs gSa fd ,d Order ysus dh izfØ;k esa nks cMh ckrsa Involved gSaA igyh Customer dh Information ysuk o nwljh Order fd, tkus okys Items dh Information ysukA bl fp= ds gj Process dks vkSj Explore djds ge Data Flow dh vkSj vf/kd Deep Details izkIr dj ldrs gSa] tSlkfd vxys nks fp=ksa esa n”kkZ;k x;k gSA bl fLFkfr esa Diagrams fdlh System dh bruh Detailed Information ns nsrs gSa] fd ,d Application Designer ml Application dks Design djus dk Plan cuk ldrk gSA Data Flow o Data Model nksuksa dks Separate j[kus ds fy, ge dqN Guide Lines dk iz;ksx dj ldrs gSaA ;s Guide Lines fuEukuqlkj gSa%

1 ,d Data Flow Diagram ;s Show djrk gS fd Data dks dkSu Use ;k Handle dj jgk gS] tcfd Data Model ,slk ugha djrk gSA

2 ,d Data Flow Diagram ;s Show djrk gS fd Business Related Data dks fdl

rjg ls o fdu ek/;eksa (People Inquiry etc.) ls Collect fd;k x;k gS] tcfd Data Model bl ckr dh tkudkjh ugha nsrk gSA

3 ,d Data Flow Diagram Data ij Perform gksus okys mu Operations dks Show

djrk gS] tks Data dks ,d :i ls nwljs :i esa Transform djrs gSa] tcfd Data Model bl ckr dks Show ugha djrk gSA

4 ,d Data Model ;s Show djrk gS fd fdlh Database ds fofHkUu Entities fdl

izdkj ls vkil esa Internally Related gSa] tcfd Data Flow Diagram bl ckr dh dksbZ tkudkjh ugha nsrk gSA



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5 ,d Data Model mu Attributes dks Show djrk gS] tks fdlh Data Entity dks Describe djrs gSa] tcfd Data Flow Diagram fdlh Entity ds Attributes dh dksbZ tkudkjh ugha nsrk gSA

,d Data Model esa fdlh Database esa Store gksus okys Data tSls fd Entities, Attributes o Entity Relationships dh tkudkjh gksrh gSA ;fn fdlh Entity ds Data dks fdlh Database esa Store ugha fd;k tk jgk gks] rks og Entity ml Database dk fgLlk ugha gksrk gSA mnkgj.k ds fy, gkykafd Music Store dk Data Flow Diagram Music Store ds ml Employee dks Show djrk gS] tks Music Store ds fofHkUu izdkj ds Data dks Handle djrk gS] ysfdu ml Employee ls lEcaf/kr fdlh izdkj ds Data dks Database esa Store ugha fd;k tk jgk gSA blfy, Music Store Database ds ER Diagram esa Employee uke dk dksbZ Entity ugha gSSA



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Schema ,d Completed Entity-Relationship Diagram fdlh Database ds Overall Logical Plan dks Represent djrk gSA Database Management System dh Hkk’kk esa bl Overall Plan dks Schema dgk tkrk gSA ;gh og rjhdk ;k Design gksrk gS] ftlesa fdlh Database dks Maintain djus okys yksx fdlh Business System dks ns[krs gSaA os Users tks bl Schema ij vk/kkfjr Database Application dks Use djrs gSa vkSj os Users tks bl Database Schema ds vk/kkj ij Application Develop djrs gSa] os nksuksa gh bl Design ds dsoy Logical Schema rd ls gh ifjfpr gksrs gSaA Data Physically fdl izdkj ls Store gksrs gSa] bl ckr dh tkudkjh bu nksuksa dks gh ugha gksrh gS] uk rks bl Logical Schema dks uk gh bl Logical Schema dks Use djus okys Users dksA Logical Schema dh Layer ds uhps Data dk Physical Storage gksrk gS] ftls DBMS Manage djrk gSA bls Physical Schema dgk tkrk gSA Physical Schema dks DBMS gh Handle djrk gSA dsoy dksbZ cgqr gh cMk DBMS gesa ;s lqfo/kk nsrk gS fd ge Physical Schema dks Control dj ldsaA bl rjhds dk lcls cMk Qk;nk ;s gS fd Database Design djus okys o mls Use djus okys] nksuksa dks gh ;s tkuus dh t:jr ugha gksrh gS fd Data Physically fdl izdkj ls Store gks jgk



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gSA bl rjhds ds dkj.k Database dks Access djuk dkQh ljy gks tkrk gS D;ksafd ge cgqr gh vklkuh ls Logical o Physical Schemas dks Change dj ldrs gSaA pwafd ge ,d Database dks rhu rjhdksa ls ns[k ldrs gSa] igyk Logical Schema ds :i esa] nwljk User ds :i esa o rhljk Physical Schema ds :i esa] blfy, vktdy dqN Database dks Three-Schema Architecture Hkh dgk tkus yxk gSA System Programmers o vU; yksx tks fd Physical Storage dks Manage djrs gSa] os okLro esa Physical Schema ds lkFk Deal djrs gSaA vkt gekjs lkeus ftrus Hkh DBMS Softwares gSa] os gesa ml DBMS esa Store gksus okys Data ds File Structure dks Control djus dh dksbZ lqfo/kk iznku ugha djrs gSaA Database Designers, Database Administrators o dqN Application Programmers Logical Schema dks Use djrs gSaA End User Interactively dke djrs gSa] ;kuh igys ls cus gq, Database System dks Application ds ek/;e ls Use djrs gSa tcfd Application Programmers Database dks User View ds vk/kkj ij ns[krs gSa vkSj End User ds fy, Database Applications Create djrs gSaA tc ge ,d ckj ER Diagram Complete dj ysrs gSa] mlds ckn Create gksus okys Conceptual Logical Schema dks Use fd, tkus okys DBMS ds vk/kkj ij Formal Data Model esa Translate djuk gksrk gSA vkt ftrus Hkh DBMS Softwares Available gSa] os lHkh Relational Data Model ij vk/kkfjr gSaA Relational Database ,d ,slk Database gksrk gS] ftldk Logical Structure Relations ds ,d Collections ds vykok dqN ugha gksrk gSA Relational Database Model dks Edgar (E. F.) Codd us Develop fd;k FkkA 1960 ds na”kd esa Dr. Codd Existing Data Models ij dke dj jgs FksA vius vuqHko ds vk/kkj ij mUgksaus ik;k fd ftrus Hkh Data Models ml le; izpfyr Fks] os lHkh dkQh tfVy o vizkd`frd rjhdksa ls Data dks Model djrs FksA pwafd os ,d xf.krK Fks] blfy, mUgksaus fofHkUu izdkj ds Relations dks Set Theory ds vk/kkj ij Mathematical Form esa Develop djuk “kq: fd;k vkSj vius Concept dks vkSj Extend djds mUgksaus Relational Database Model Develop fd;k vkSj 1970 esa yksxksa ds lkeus yk;kA Mathematical Set Theory esa Rows (Tuple) o Columns (Attributes) ls cuh ,d Table dks ,d Relation ds :i esa Define fd;k tkrk gSA Relation dks nwljs “kCnksa esa ge Table Hkh dg ldrs gSaA ;s Definition dsoy bl ckr dks Specify djrk gS fd fdlh Table ds gj Column esa D;k Store fd;k tk,xk] ysfdu mlesa Actual Data dks Specify ugha fd;k tkrk gSA tc ge bl Table esa Data ds Rows Include djrs gSa] rc gesa ml Relation dk ,d Instance izkIr gksrk gSA mnkgj.k ds fy, ge fdlh Student ds Relation dks fuEukuqlkj Represent dj ldrs gSa%

igyh utj esa ;s Relation ,d Flat File ;k fdlh Spreadsheet ds Rectangular Portion dh rjg gh fn[kkbZ nsrk gSA ysfdu tc ge bl Table dks Set Theory ds vk/kkj ij ,d



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Relation ds :i esa ns[krs gSa] rc bl Relation ds dqN cgqr gh Specific Characteristics gesa fn[kkbZ nsrs gSaA Set Theory ds vk/kkj ij ns[kus ij bl Relation dk gj Column DBMS esa Store fd, tkus okys Constraints dks Represent djrk gSA tc ge Set Theory ds vk/kkj ij fdlh Relation ds ,d Column dh Characteristics dks ns[krs gSa] rc gesa ,d Column dh fuEu Characteristics gksrh gSa%

1 ,d Table esa gj Column dk ,d Unique uke gksrk gSA fdlh ,d gh Relation Schema esa nks ;k nks ls vf/kd Tables esa ,d gh uke ds Columns gks ldrs gSa] ysfdu fdlh ,d gh Table esa ,d gh uke ds nks Column ugha gks ldrs gSaA tc leku uke dk dksbZ Column ,d ls T;knk Tables esa Appear gksrk gS vkSj leku uke ds Columns dks Hold djus okys Tables tc leku Data Manipulation Operation ds fy, Use fd, tkrs gSa] rc gesa mu leku uke ds Columns dks Particular Table ls Access djus ds fy, muds Tables ds uke dks milxZ ds :i esa Columns ds uke ls igys Use djuk iMrk gS vkSj Columns ds uke dks Table ds uke ls ,d Dot ;k Period }kjk tksMuk iMrk gSA tSls%

Customers.CustID Students.StudID

2 ,d Column gesa”kk flQZ ,d gh Domain ds eku dks Store djrk gSA

fdlh Table esa ftl Column dks ftl Type dk eku Store djus ds fy, Define fd;k tkrk gS] og Column dsoy mlh eku dks Store djrk gSA mnkgj.k ds fy, fdlh Student Table esa Student dk uke Store djus ds fy, ftl Column dks Define fd;k x;k gS] og Column dsoy uke Store djus ds fy, gh Use fd;k tk ldrk gS] tcfd tks Column Roll Number Store djus ds fy, Define fd;k x;k gS] mlesa dsoy Roll Number gh Store fd;k tk ldrk gSA ;kuh gj Column esa fdlh ,d fuf”pr Domain ds eku dks gh Store fd;k tk ldrk gSA ifj.kkeLo:i Relations dks Column Homogeneous dgk tkrk gSA lkFk gh Table dk gj Column fdlh uk fdlh Domain Constraint ls Associated gksrk gSA gekjs DBMS ds vk/kkj ij Domain Constraint Data Type dh rjg gh Simple gksrk gS] tSls fd Integers, Characters, Date vkfnA blds vykok gekjk DBMS bl ckr dh Hkh lqfo/kk nsrk gS fd ge gekjh t:jr ds vk/kkj ij u;k Domain Hkh Create dj ldrs gSa vkSj mls viuh Table ds fdlh Column ds lkFk Attach dj ldrs gSaA

Columns dh rjg gh Rows dh Hkh fdlh Relation esa viuh dqN Special Properties ;k Characteristics gksrh gSaA ;s Characteristics fuEukuqlkj gSa%

1 ,d Row ds fofHkUu Column esa ge flQZ vkSj flQZ ,d gh eku dks Store dj ldrs gSaA ;kuh fdlh Row dk gj Column Single-Valued gksrk gSA vkSj



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2 ,d Relation esa gj ,d Record Unique gksrk gSA ;kuh ,d Relation esa ,d Row dk nqckjka Duplication ugha gks ldrkA fdlh Relation ds gj Record dks Unique cukus ds fy, DBMS Lo;a gh gj ROW ds lkFk Unique Constraint dks Enforce ugha djrk gS] cfYd bl lqfo/kk dks ge Primary Key }kjk izkIr djrs gSaA

3 Primary Key fdlh Table ds fdlh Column ;k Columns dk Combination gksrk

gS] ftls ml Table ;k Relation ds fdlh Record ;k Row dks Uniquely Identify djus ds fy, Define fd;k tkrk gSA tSls gh fdlh Relation esa dksbZ Unique Primary Key dks fdlh fof”k’V Column ;k Columns ds Combination ds lkFk Set dj fn;k tkrk gS] oSls gh ;s fuf”pr gks tkrk gS] fd ml Table dk gj Record ;k Row Unique gksxkA

Tables ,d Relational Database nks rjg ds Tables ds lkFk izfØ;k djrk gS] ftUgsa Base Table o Relation dgrs gSaA ;s nksuksa gh Database esa Store gksrs gSaA ;s gh os Tables gksrs gSa] tks gekjs Database dk Conceptual Logical Schema cukrs gSaA blds vykok Tables ij ftu Relational Operations dks Perform fd;k tkrk gS] muds ifj.kkeLo:i dqN Additional Tables Produce gksrs gSaA ;s Tables flQZ RAM ;k Main Memory esa Exist gksdj viuk dke iwjk djrs gSa vkSj fQj Destroy gks tkrs gSa] blfy, bUgsa Virtual Tables dgk tkrk gSA Virtual Tables ,d Legal Relation ugha gksrs gSa] D;ksafd buesa Primary Keys dks Define ugha fd;k tk ldrk gSA ysfdu pwafd Virtual Tables Database esa Store ugha gksrs gSa] blfy, ;s Database Design esa fdlh rjg dh dksbZ leL;k iSnk ugha djrs gSaA Virtual Tables DBMS dks dbZ rjhdksa ls Qk;nk igqapkrs gSaA lcls igys rks ;s Tables DBMS dks Application dh Processing ds nkSjku Generate gksus okys Intermediate Query Result dks Database esa Store djus ds ctk; bu Virtual Tables esa Store djds Main Memory esa Store djus dh lqfo/kk nsrs gSa] ftlls Query dh Performance vPNh gks tkrh gS] D;ksafd Main Memory dh Speed gesa”kk gh Disk dh Speed ls T;knk gksrh gSA DBMS dk nwljk Qk;nk ;s gksrk gS fd tks Tables Relational Data Model ds Rules dks Violate djrs gSa] DBMS mUgsa Virtual Tables ds :i esa Main Memory esa Store djds Manage djrk gS] ftlls Actual Database esa Stored Data dh lqj{kk dks fdlh izdkj dk dksbZ [krjk ugha jgrkA rhljk vkSj vfUre Qk;nk ;s gksrk gS fd DBMS }kjk Virtual Tables ds iz;ksx ds dkj.k ckj&ckj Disk ij Write/Read/Delete Operations dks Perform ugha djuk iMrk gS] ftlls Disk ij Data Fragments ;k dbZ VqdMksa esa Store ugha gksrk gSA blls le; dh Hkh cpr gksrh gS vkSj Database dk Performance Hkh vPNk gks tkrk gSA Virtual Tables dks lkekU;r;k Temporary Tables ;k Temporary Base Tables Hkh dgk tkrk gSA fdlh Relation dks Represent djrs le; mlesa Data dks Store ugha fd;k tkrk gSA bl fLFkfr esa fdlh Relation dks Represent djus dk ,d Common rjhdk fuEukuqlkj gksrk gS% RelationName ( PrimaryKeyColumn, NonPrimaryKeyColumn1, ... , NonPrimaryKeyColumnN)



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mnkgj.k ds fy, ;fn ge fdlh Customer Relation dks Represent djuk pkgsa] rks fuEukuqlkj dj ldrs gSa% Customers (CustID, FName, LName, Phone) blh rjg ls ;fn ge fdlh Student ds Relation dks Represent djuk pkgsa] rks mls Hkh fuEukuqlkj Represent dj ldrs gSa% Students (SrNo, Name, FName, Add, City, State, DOB, DOJ) ;s nksuksa Expressions fdlh Relation ds Structure dks Represent djus ds Ideal Expressions gSa] ftuesa dksbZ Data ugha gSA ;fn fdlh Relation esa Data Included gksa] rks ,slk Relation og Expression ml Relation dk ,d Instance gksrk gSA

Primary Keys tSlkfd geus igys Hkh crk;k fd Primary Key fdlh Table fd izR;sd Record ;k Row dks Uniquely Identify djuk lEHko cukrk gSA fdlh Relation esa Primary Key dh ogh Hkwfedk gksrh gS] tks fdlh Entity Identifier dh gksrh gSA Primary Key dks Define djds ge ;s r; djrs gSa fd geus ftl NksVs ls NksVs Data dks Database esa Store fd;k gS] ge ml NksVs ls NksVs Data ds VqdMs dks Hkh fQj ls izkIr dj ldsaxsA tc ge Relational Database dh ckr djrs gSa] rc fdlh Database ls fdlh Data ds NksVs ls NksVs VqdMs dks Hkh izkIr djus ds fy, gesa flQZ rhu ckrksa dh tkudkjh gksuh pkfg,% ml Table ds uke dh] ftlesa Data Stored gS] ml Column ds uke dh] ftlls ge Data dks izkIr djuk pkgrs gSa vkSj ml Row ds Primary Key dh] ftlds Column ds Data dks ge izkIr djuk pkgrs gSaA ;fn gj Row ds fy, Primary Key Unique gks] rks ge bl ckr ds fy, Sure gks ldrs gSa fd ge Exact Row ls Data dks Retrieve dj ldsaxsA ysfdu ;fn gj Row Unique uk gks] rks ge ,d ls T;knk Rows dks Retrieve djsaxs] tgka ;s r; djuk eqf”dy gks tk,xk] fd gekjk Required Data fdl Row esa gSA pwafd ,d Primary Key gesa”kk fdlh Record ;k Row dks Uniquely Identify djus ds fy, Define fd;k tkrk gS] blfy, fdlh Hkh Primary Key Column dks Empty ugha NksMk tk ldrk ;k fdlh Primary Key Field esa NULL Store ugha fd;k tk ldrk gSA Null ,d Special Database eku gksrk gS] ftldk eryc “Unknown” gksrk gSA ;fn gekjs Relation esa dsoy ,d gh Record gks vkSj ge Primary Key Filed dks Null dj nsa] rks dksbZ Problem Generate ugha gksrh gS] ysfdu tSls gh ge ml Relation esa nwljk Record Enter djsaxs] ge Primary Key Fields ds Uniqueness dh Property dks [kks nsaxsA blfy, ge dHkh Hkh fdlh Table ds Primary Key Field dks Null Assign ugha dj ldrs gSaA bl Constraint dks Entity Integrity dgk tkrk gS vkSj Database esa ftruh ckj Hkh Data Enter ;k Modify fd;k tkrk gS] DBMS Primary Key dks Enforce djds Database ij Apply djrk gS] ftlls gj Record gesa”kk Unique cuk jgrk gSA



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ge fdlh Primary Key Field esa Duplicate Data Store ugha dj ldrs gSaA ;fn ge ,slk djus dh dksf”k”k djrs gSa] rks Hkh DBMS gesa ,slk ugha djus nsrk gS] D;ksafd og Primary Key ds Constraint dks Follow djrk gS] ftlds rgr ,d Column esa dHkh Hkh Duplicate Values Store ugha gks ldrh gSA fdlh Relation ds fy, ,d mfpr Primary Key Select djuk ,d Challenging dke gksrk gSA dqN Entities esa Natural Primary Keys gksrh gSa] tSls fd Purchase Order ;k Invoice dks Identify djus ds fy, gesa”kk ,d Meaningless Unique Number gksrk gS] ftlls dksbZ Particular Purchase Order ;k Invoice Identify gksrk gSA bls gh Natural Primary Key dgk tkrk gS vkSj ;s gh ,d Ideal Primary Key dk mnkgj.k gksrk gSA ge fdlh Hkh Entity ds mlh Attribute dks fdlh Relation esa Primary Key ds :i esa Identify dj ldrs gSa] ftldh fuEukuqlkj nks fo”ks’krk,a gksa%

• Primary Key dh Value dHkh Hkh Change ugha gksrh gSA (Uniqueness) • Primary Key Column dks Null ugha j[kk tk ldrk gSA (Not Null)

ge fdlh Entity ds fdlh ,sls Field dks Primary Key Set ugha dj ldrs gSa] ftudk Repetition lEHko gksA mnkgj.k ds fy, ;fn ge fdlh Customer Relations esa Customer ds Name Filed dks Primary Key Set dj nsa] rks DBMS esa Enter fd, ,d uke ds ,d gh O;fDr dks Database esa Store gksus nsxkA D;ksafd DBMS Primary Key Field esa ,d gh Value dk Repetition ugha djus nsrk gS] tcfd ,d gh uke ds nks Customer gks ldrs gSaA blh rjg ls ge ml Attribute dks Hkh Primary Key Set ugha dj ldrs gSa] tks ckj&ckj Change gksrk gSA bl fLFkfr esa fdlh ,d gh Entity ds ,d gh Instance dks ,d gh Relation esa ,d ls T;knk ckj Enter fd;k tk ldrk gS] ftlls Database dh Consistency o Accuracy izHkkfor gksrh gSA bl lEca/k esa ge igys Hkh ppkZ dj pqds gSaA ,d Appropriate Primary Key dks Choose djus ds fy, gesa gesa”kk fdlh Entity ds Meaningful Attributes dks Avoid djuk pkfg,A fdlh Meaningful Information dks Code ds :i esa Specify djds mls fdlh Relation esa Primary Key ds :i esa Use ugha djuk pkfg,] tSlkfd geus Music Store Database esa fd;k FkkA bl rjg ds Code dks Decode djus esa leL;k,a iSnk gks ldrh gSa ;k bl rjg ds Codes dks cukus esa Hkh xyfr;ksa dh lEHkkouk jgrh gSA lkFk gh Meaningful Information Change gksus dh Hkh lEHkkouk jgrh gS] tSlkfd Music Store Database ds lUnHkZ esa crk;k x;k gSA fdlh Primary Key ds mijksDr nks xq.kksa ds vykok ;s Primary Key dk rhljk xq.k gksrk gS fd%

• ,d Primary Key ds :i esa Meaningful Data dks Avoid djuk pkfg,A gkykafd t:jr ds vk/kkj ij o vPNh rjg ls lksap&fopkj dj ysus ds ckn ;fn gesa yxrk gS] fd fdlh Meaningful Data dks Primary Key cuk;k tk ldrk gS] rks ge fdlh Meaningful Data dks Hkh Primary Key ds :i esa Specify dj ldrs gSaA dbZ ckj fLFkfr;ka Hkh ,slh gh gksrh gSa] tgka ij fdlh fo”ks’k vFkZ okys Meaningful Data dks gh Primary Key cukuk t:jh gksrk gSA mnkgj.k ds fy, ;fn gesa fdlh ?kVuk dks Time ;k Date ds lkFk Specify djuk gks] rks gesa Date ;k Time tSls Meaningful Data dks Primary Key ds :i esa Use djuk t:jh gks tk,xkA



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Composite Keys dbZ Tables ,sls gksrs gSa] ftuesa dksbZ Hkh ,slk Single Column ugha gksrk gS] ftlesa Values dk Duplication uk gksA mnkgj.k ds fy, ;fn ge Order Lines ds Table dks ns[ksa] rks pwafd ,d Order esa ,d ls T;knk Items Appear gks ldrs gSa] blfy, Order Numbers Hkh ,d ls T;knk ckj Repeat gksrk gS] blh rjg ls ,d gh Item ,d ls T;knk Order ij Appear gks ldrk gS] blfy, Item Number Hkh ,d ls T;knk ckj Repeat gksrk gS] tSlkfd ge fuEu Table esa ns[k ldrs gSaA blfy, bl Table dk dksbZ Hkh ,d Single Column Primary Key dh rjg Use ugha fd;k tk ldrkA

OrderID ItemID Quantity 10999 1122 1 10999 2211 3 10999 1002 1 10990 1122 2 10990 2211 4 10993 1122 1 10993 1100 2 10995 1100 1

fQj Hkh ;fn ge Order Number o Item Number dks Combined Form esa Use djsa] rks ;s fdlh Row ;k Record dks Uniquely Identify dj ldrs gSaA tc fdlh Table esa nks ;k nks ls T;knk Columns dks Combined :i ls Primary Key ds :i esa Use djds fdlh Record ;k Row dks Uniquely Identify djrs gSa] rks bl Columns ds Group dks Composite Key dgk tkrk gSA gkykafd ;fn ge pkgsa rks bl Table ds rhuksa gh Columns dks Combined Form esa Use djds fdlh Record ;k Row dks Uniquely Identify dj ldrs gSa] ysfdu bl Table esa fdlh Record dks Uniquely Identify djus ds fy, dsoy Order Number o Item Number dk Combination gh i;kZIr gS] blfy, bl Composite Key esa Quantity Column dks Add djus dh t:jr ugha gSA tc ge Composite Key dk iz;ksx djds fdlh Record dks Uniquely Identify djuk pkgrs gSa] rc gesa ljyrk ds fy, dqN ckrksa dks /;ku esa j[kuk pkfg,] ftlls Database Design esa fdlh rjg dh dksbZ ijs”kkuh iSnk uk gksA ;s ckrsa fuEukuqlkj gSa%

1 ,d Composite Primary Key esa tgka rd lEHko gks] de ls de Columns dk iz;ksx djuk pkfg,A ;kuh ;fn nks Columns ds Group ls Table ds gj Record dks Uniquely Identify fd;k tk ldrk gS] rks rhu Columns dks feykdj Primary Key ugha cukuk pkfg,A

2 tgka rd lEHko gks] Composite Primary Keys dks Meaningless j[kuk pkfg,A

ge Relations Hkh Create dj ldrs gSa] ftlds lHkh Columns dks feykdj ,d Key cuk fy;k x;k gksA mnkgj.k ds fy, ge ,d Library Card Catalog dks ysrs gSaA fdlh Library esa ftruh Hkh Books gksrh gSa] mu lHkh Books dk ,d Unique ISBN (International Standard Book Number) gksrk gSA



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fdlh Library Catalog esa lHkh ISBN Number dh Book ds lkFk ,d Subject Heading ;k fo’k; dks Associate fd;k x;k gksrk gS vkSj gj Book ds lkFk ,d Subject Heading ;k fo’k; dks Associate fd;k x;k gksrk gSA bl rjg ls ,d Book o mlds Subject Heading ds chp Many To Many dh Relationship Create gks tkrh gSA bl Relationship dks ge fuEukuqlkj Represent dj ldrs gSa% SubjectCatalog ( ISBN, SubjectHeading) bl Relationship dks Create djus ds fy, gesa dsoy gj Subject Heading dks ,d Book Identifier ds lkFk ,d Pair ds :i esa Specify djuk gksrk gSA bl fLFkfr esa bl Table ds nksuksa Columns Primary Key ds fgLls cu tkrs gSaA ge ns[k ldrs gSa fd bl Table ds lHkh Fields dks Composite Primary Key ds :i esa Use dj fy;k x;k gSA bl rjg dh Relationship ls Database ds Design esa dksbZ Problem ugha gksrh gSA okLro esa tc Hkh fdlh Database esa dksbZ Composite Entity gksrk gS] ftlesa dksbZ Relationship Data ugha gksrk] rc bl izdkj dh Relationships dks Define djus ij Design lEcaf/kr fdlh izdkj dh dksbZ leL;k iSnk ugha gksrh gSA bl izdkj ds Composite Entity dks lkekU;r;k Many To Many dh Relationship dks Represent djus ds fy, cuk;k tkrk gSA

Representing Data Relationships fiNys dbZ mnkgj.kksa esa geus fofHkUu izdkj ds Primary Key Identifiers dks Use fd;k gSA bu Keys ds vk/kkj ij gh Relational Database fofHkUu Entities ds chp dh Relationships dks Represent djrk gSA bl Concept dks Clear djus ds fy, fuEu rhu Tables dks nsf[k,] ftuesa Data dks Fill fd;k x;k gS% Items Table

ItemID Title DistID Price 2001 C in Hindi 200 200.0 2002 C++ in Hindi 200 225.0 2003 Java in Hindi 300 300.0 2004 DBMS in Hindi 400 150.0

Orders Table OrderID CustID OrderDate 600000 00001 12/02/2006 600001 01000 15/06/2007 600002 00100 20/12/2008 Orders Lines Table OrderID ItemID Quantity Shipped? 600000 2001 1 Y 600000 2002 1 Y 600001 2002 2 Y 600002 2002 1 N 600002 2003 2 N 600002 2001 1 N



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;gka Describe dh xbZ lHkh Tables “Music Store” Database ds ER Diagram ds leku gh gSaA ;gka Orders Table (Orders Entity) ds gj Unique Instance dks OrderID uke ds ,d Primary Key }kjk Identify fd;k x;k gS] tks fd ,d Meaningless Data gSA Items Table (Items Entity) esa gj Item dks ,d Unique Item Number }kjk Identify fd;k tkrk gS] ftls ItemID uke fn;k gS vkSj ;gka Hkh ;s ,d Meaningless Data gSA rhljh Table Order Lines (Order Lines Entity) gS] tks Music Store dks ;s crkrk gS fd dkSulk Item fdl Order dk fgLlk gSA tSlkfd geus Composite Entity ds ckjs esa crk;k] ;s ,d Composite Entity gS vkSj bl Table dks ,d Composite Primary Key dh t:jr gksrh gS] D;ksafd Multiple Orders ij Multiple Items Appear gks ldrs gSaA bl Composite Primary Key dk mu vU; Primary Keys dh rqyuk esa vf/kd egRo gS] ftUgsa fdlh Table ds gj Instance ;k Row ;k Record dks Uniquely Identify djus ds fy, Define fd;k tkrk gSA bl Table esa ;s Composite Key gj Row dks Uniquely Identify djus ds lkFk gh Order Lines, Orders o Items ds chp dh Relationship dks Hkh Represent djrk gSA Order Lines Relation esa ItemID Column mlh rjg dk Primary Key gS] ftl rjg dk Item Table ij gSA ;s Primary Key nks Tables ds chp One To Many dh Relationship dks Represent djrk gSA blh rjg ls Orders o Order Lines ds chp Hkh ,d One To Many dh Relationship gS] D;ksafd Order Lines Table dk OrderID mlh rjg dk Primary Key gS] ftl rjg dk Orders Table esa gSA tc fdlh Table esa oSlk gh Primary Key gksrk gS] tSlk fdlh nwljh Table esa gksrk gS] rks bl izdkj ds Key dks Foreign Key dgk tkrk gSA fdlh Relational Database esa fdlh Foreign Key dk fdlh Primary Key ds lkFk Connect ;k Match gksuk] Relationship dks Represent djrk gSA fdlh Relational Database esa Columns ;k Keys dh Matching ds vykok ,slk dksbZ Structure ugha gksrk gS] ftlls Relationship dks Represent fd;k tk ldsA ;kuh fdlh Relational Database esa Columns ;k Keys dh Matching ls gh fofHkUu Entities ds chp dh vkilh Relationship dks Represent fd;k tkrk gSA fdlh Relational Database esa fofHkUu Tables ds chp dh Relationship Logical Lrj ij gh gksrh gS] bl izdkj dh Relationship dk Physical Lrj ij dksbZ vfLrRo ugha gksrk gSA Foreign Keys fdlh Composite Primary Key dk fgLlk gks ldrs gSa ;k os muds Table ds Primary Key dk fgLlk ugha Hkh gks ldrs gSaA ;kuh ekuyks fd Music Store ds Customers o Orders ds chp fuEu Relation gS% Customers ( CustID, FName, LName, Telephone) Orders ( OrderID, CustID, OrderDate) bl Relationship esa Orders Table esa tks CustID Column gS] og Foreign Key gS] ftls Customer Table ds Primary Key CustID ls Match fd;k x;k gSA ;gka Customers o Orders ds chp One To Many dh Relationship Represent gks jgh gSA fQj Hkh Orders



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Table dk CustID Column Orders Table ds Primary Key dk fgLlk ugha gS] cfYd ;s ,d Non-Key Attribute gS] blfy, ;s ,d Foreign Key gSA rduhdh :i ls Foreign Keys esa rc rd fdlh eku dks Store ugha fd;k tk ldrk gS] tc rd fd os fdlh Composite Primary Key dk fgLlk ugha gksrs gSaA bUgsa Null Assign fd;k tk ldrk gSA ysfdu gekjs Music Store Database esa ;fn ge CustID Foreign Key dks Null Assign djrs gSa] rks xEHkhj leL;k,a iSnk gks ldrh gSa] D;ksafd ;fn Orders Table esa CustID Foreign Key dks Null Assign fd;k tkrk gS] rks ;s irk yxkus dk dksbZ rjhdk ugha cprk gS] fd ml Order dks fdl Customer us Place fd;k gSA Primary Keys o Foreign Keys dh Matching ds vk/kkj ij gh ,d Relational DBMS fofHkUu izdkj dh Relationships dks Represent djrk gSA mnkgj.k ds fy, ekuyks fd Music Store dk dksbZ Employee ;s tkuuk pkgrk gS fd Order Number #600000 ij fdl Title dk Order fd;k x;k gSA bl fLFkfr esa DBMS Line Items Table esa lcls igys mu Rows dks Identify djrk gS] ftuesa Order Number #600000 Stored gSA fQj DBMS mu Identified Rows esa ls Item Numbers dks Select djrk gS vkSj mUgsa Items Table ds Item Numbers ls Match djrk gSA ftl Row esa nksuksa Item Numbers Match gksrs gSa] DBMS ml Row ls Associated Title dks Retrieve dj ysrk gSA

Referential Integrity fiNys Paragraph esa Data ds Access gksus dk tks rjhdk crk;k x;k gS] og rjhdk rc rd vPNs rjhds ls dke djrk gS] tc rd fdlh dkj.ko”k dksbZ ,slk Record Orders Table esa ugha gksrk gS] ftlesa OrderID Filed esa Null gksA D;ksafd ;fn Order Table esa OrderID Field esa Null Stored gks] rks ml Row ls Match gksus okyk dksbZ Record Order Lines Table esa izkIr ugha gksxkA ;s ,d cgqr gh vokafNr fLFkfr gksrh gS] D;ksafd bl fLFkfr esa Order fd, x, Items dks Ship ugha fd;k tk ldrk gS] D;ksafd bl fLFkfr esa ,slk dksbZ rjhdk ugha gksrk gS] ftlls ;s irk yxk;k tk lds] fd ml Order dks fdl Customer us Place fd;k gSA blfy, bl izdkj dh fLFkfr;ksa ls cpus ds fy, Relational Data Model Referential Integrity uke ds ,d Constraint dks Enforce djrk gS] tks ;s r; djrk gS fd gj Non-Null Foreign Key Value fdlh Existing Primary Key Value ls t:j Match gksA fdlh Relational Database esa Use fd, tkus okys lHkh Constraint dh rqyuk esa ;s lcls T;knk egRoiw.kZ Constraint gksrk gS] D;ksafd ;s Database ds fofHkUu Entities ds chp ds Cross-Reference dh fo”oluh;rk ;k Constancy dks lqfuf”pr ;k Ensure djrk gSA Referential Integrity Constraints Database esa Stored gksrs gSa vkSj bUgsa DBMS }kjk Enforce fd;k tkrk gSA vU; Constraints dh rjg gh] User tc Hkh Database esa Stored fdlh Data dks Modify djus dh dksf”k”k djrk gS ;k Database esa u;k Data Enter djrk gS] DBMS bl Constraint dks Check djrk gS vkSj bl ckr dk Verification djrk gS fd ml Data ls lEcaf/kr lHkh Entities vkil esa iwjh rjg ls Compatible gSaA ;kuh gj Foreign Key mlds Primary Key ls Matched gSA



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;fn bl Input fd, tkus okys ;k Modify fd, tkus okys Data }kjk bl Constraint dks Violet fd;k tkrk gS] rks DBMS ml Data Modification ;k Insertion dks Allow ugha djrk vkSj Database esa fLFkr fdlh Hkh Entity ds fdlh Hkh Data dks fdlh Hkh izdkj ls Change ugha djus nsrk gSA gesa”kk ;s t:jh ugha gksrk gS fd fdlh Table dh Foreign Key gesa”kk fdlh nwljh Table ds Primary Key ls gh Refer gks] cfYd Foreign Key dks dsoy ,d Primary Key ds Reference dh gh t:jr gksrh gS] blfy, ge ,d Foreign Key ds lkFk mlh Table dh Primary Key dk Reference Hkh Set dj ldrs gSa] ftlesa og Foreign Key Stored gSA mnkgj.k ds fy, fuEu Employee Relation dks nsf[k,% Employee ( EmpID, FName, LName, Dept, MngrID) pwafd Manager Hkh ,d Employee gh gksrk gS] blfy, gkykafd bl Relation esa MngrID dks EmpID ls vyx uke fn;k x;k gS] ysfdu fQj Hkh okLro esa MngrID ,d Foreign Key gS] tks fd viuh gh Table ds Primary Key dks Refer dj jgk gSA blfy, ftruh ckj Hkh ,d User ,d MngrID Input djrk gS] DBMS gj ckj bl ckr dks Ensure djrk gS fd og Manager ,d Employee dh rjg ml Table esa igys ls gh Exist gSA

Views os yksx tks fd fdlh Database Schema dks Develop djus ds fy, ftEesnkj gksrs gSa] ;k os yksx tks vU; lkekU; Users ds fy, Application Programs Develop djrs gSa] os lkekU;r;k Database Schema o Database dh Base Tables ds lkFk Directly dke dj ldrs gSaA ysfdu tks End Users gksrs gSa] mUgsa Application Programs ;k Database Schema ds ckjs esa iwjh tkudkjh ugha gksrh gS] blfy, lkekU;r;k bUgsa Database dh Base Tables dks Directly Use djus ls jksdk tkrk gSA pwafd End User dks dHkh Hkh Database Schema o Application Program ds ckjs esa iwjh tkudkjh ugha gksrh gS] blfy, ;fn os Database dh Base Tables ds lkFk Directly dke djrs gSa] rks gks ldrk gS fd os vius Database dh Tables esa Stored Data dks xyrh ls Corrupt dj nsaA blfy, Data dh lqj{kk ds fy, End Users dks Database dh Base Tables ds lkFk Directly dke djus dk vf/kdkj Database Developer }kjk ugha gksrk gSA blfy, Relational Data Model ,d ,slk rjhdk Provide djrk gS] ftlesa gj User dks Database esa mldk Lo;a dk ,d Window feyrk gS vkSj gj End User mlh Window esa viuk dke djrk gSA ;s Window Database Design dh lHkh Details dks User ds fy, Hide dj nsrk gS] ftlls ,d End User dHkh Hkh Database dh Base Tables dks Direct Access ugha dj ikrk gS vkSj Database dk Data End User dh xyrh ls Damage gksus ls gesa”kk cpk jgrk gSA View Hkh ,d rjg dk Table gh gksrk gS] ysfdu ;s Data ds lkFk Database esa Store ugha gksrk gSA cfYd ;s ,d uke ds lkFk Data Dictionary esa Store gksrk gSA blesa gesa”kk dksbZ Database Query gksrh gS] ftlds vk/kkj ij dksbZ View Database ls viuk Data Retrieve djrk gSA ,d View esa ,d ls T;knk Tables, Rows o Columns ds Data gks ldrs gSaA



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gkykafd ,d View dks fdlh Hkh Database Query ds vk/kkj ij Create fd;k tk ldrk gS] ysfdu dbZ Views dks dsoy Data Display djus ds fy, gh Create fd;k tkrk gSA fdlh Hkh Database ds Data dks Modify djus ds fy, Views dks Create ugha fd;k tkrk gSA Views dks bl rjhds ls Store djus dk lcls cMk Qk;nk ;s gS fd tc Hkh User fdlh Data Manipulation Language (SQL Statement) esa View dk uke Include djrk gS] rc DBMS ml View Name ls Associated Query dks Execute djrk gS vkSj View ds Table dks fQj ls Recreate djrk gSA bldk eryc ;s gS fd View esa gesa”kk Current Data gh gksrk gSA ,d View Table Main Memory esa rHkh rd miyC/k jgrk gS] tc rd dksbZ Data Manipulation Language (SQL Statement) Execute gksrk gSA tSls gh User nwljk SQL Statement Use djds nwljh Query Create djrk gS] fiNyh Query dh View Table Main Memory ls Remove gks tkrh gS vkSj Generate gksus okyk u;k Result View esa Stored ml fiNyh Query ds Result dks Replace dj nsrk gSA blfy, ,d View Table gesa”kk ,d Virtual Table gksrh gSA dqN DBMS ;s lqfo/kk nsrs gSa fd View Table ds Contents dks Base Table dh rjg Store fd;k tk ldrk gSA ysfdu fdlh View Table dks Base Table cukus dk dksbZ fo”ks’k Views dks bl rjhds ls Store djus dk lcls cMk Qk;nk ;s gS fd tc Hkh User fdlh Data Manipulation Language (SQL Statement) esa View dk uke Include djrk gS] rc DBMS ml View Name ls Associated Query dks Execute djrk gS vkSj View ds Table dks fQj ls Recreate djrk gSA bldk eryc ;s gS fd View esa gesa”kk Current Data gh gksrk gSA ,d vkSfpR; ugha gksrk gS] D;ksfd ,sls DBMS Softwares esa Hkh fdlh View Table ls Create dh xbZ Base Table dks ml fLFkfr esa Automatically Update djus dh lqfo/kk ugha gksrh gS] tc ml Table esa Change fd;k tkrk gS] ftlds vk/kkj ij View Table dks cuk;k x;k FkkA ;kuh ;fn fdlh Table X ls ,d View Table Y dks Create fd;k tkrk gS vkSj bl View Table dks Base Table ds :i esa Database esa Store dj fy;k tkrk gS vkSj mlds ckn Table X esa dksbZ ifjorZu fd;k tkrk gS] rks bl View Table Y ls Create gksus okyh Base Table Y esa dksbZ Automatic Updation ugha gksrk gSA blfy, tSls gh ge Base Table X esa dksbZ ifjorZu djrs gSa] Base Table Y ds Data gekjs Database ds fy, Out Of Date gks tkrs gSa] ftudk gekjs Database ds fy, dksbZ Meaning ugha jg tkrk gSA vc ,d loky fnekx esa vk ldrk gS fd tc Data dks Store djus ds fy, ,d Base Table Create fd;k gh tkrk gS] rks Views dks Use djus dh D;k t:jr gSA rks Views dks Use djus ds rhu vPNs dkj.k gSa%

1 tSlkfd igys crk;k x;k fd Views dk iz;ksx djus ls Data dh Security dk Feature izkIr gksrk gS] D;ksafd Views dk iz;ksx djds End User dHkh Hkh Database ds Schema ds lkFk fdlh izdkj dh dksbZ izfØ;k ugha dj ldrk gSSA

2 Views mu yksxksa ds fy, Database dk Design le>uk ljy cuk nsrk gS] tks fdlh

Database Schema ds vk/kkj ij Application Programs Develop djrs gSaA



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3 pwafd Views ,d ,slh Query gksrh gSa] ftudk ,d uke gksrk gS] blfy, budk iz;ksx ,slh Complex Queries dks Store djus ds fy, fd;k tk ldrk gS] ftUgsa ckj&ckj Use djuk gksrk gSA fQj mu Complex Queries dks Use djus ds fy, gesa dsoy ml View ds uke dks gh Use djuk gksrk gSA

Relational Database ds vU; Structural Elements dh rjg gh Views dks Hkh fdlh Hkh le; Create o Destroy fd;k tk ldrk gSA pwafd Views esa fdlh izdkj dk Stored Data ugha gksrk gS] cfYd fdlh ,slh Query dk Specification gksrk gS] ftlds vk/kkj ij Virtual Table Create gksrh gS] blfy, Views dks Add djus ;k Delete djus ij bldk Database dh Base Tables o Tables esa Stored Data ij dksbZ izHkko ugha iMrk gSA fdlh View dks Remove djus ij dsoy rHkh leL;k iSnk gks ldrh gS] tc ml View dks fdlh Application Program esa Use fd;k x;k gks vkSj Program dks bl izdkj ls Modify uk fd;k x;k gks fd og ml View ds fcuk Hkh fdlh vU; View ;k Base Table ds vk/kkj ij Bhd rjhds ls dke dj ldsA

Data Dictionary gj DBMS esa ,d Data Dictionary ;k Catalog gksrk gSA Relational Database dk Structure blh Catalog ;k Data Dictionary esa Store gksrk gSA Data Dictionary Relations ds lewg ls cuh gksrh gS vkSj gekjs Database ds lHkh Elements bl Data Dictionary Relation esa mlh rjg ls Store gksrs gSa] ftl rjg ls ,d Entity ds Relation esa fofHkUu Data Store gksrs gSaA ;kuh Data Dictionary Relation esa Database ds lHkh Relations Data dh rjg Store gksrs gSaA ge Data Dictionary Relation dh Hkh mUgha Tools dk iz;ksx djds Query dj ldrs gSa] ftu Tools dk iz;ksx djds fdlh lkekU; Relation dh Query djrs gSaA dksbZ Hkh User Data Dictionary Tables dks Directly Modify ugha dj ldrk gSA fQj Hkh ftu Data Manipulation Language Commands (SQL Commands) dk iz;ksx ge Database ds Elements dks Create o Destroy djus ds fy, djrs gSa] mUgha Commands dk iz;ksx ge Data Dictionary Tables ds Rows dks Modify djus ds fy, Hkh dj ldrs gSaA gesa Data Dictionary esa fuEu izdkj dh Information izkIr gksrh gSa%

1 gj Table dks Create djus okys Columns dh Definitions dh Information 2 Relations ij Apply fd, x, Integrity Constraints dh Information 3 Security Information tks ;s crkrh gS fd dkSulk User fdl Table ij fdl izdkj ds

Operations dks Perform dj ldrk gSA 4 Database Structure Elements tSls fd View o vU; User Defined Domains dh

Information User tc Hkh fdlh Hkh rjhds ls Data dks Access djus dh dksf”k”k djrk gS] Relational DBMS lcls igys Data Dictionary esa ;s r; djus ds fy, tkrk gS fd User us ftl Database Elements dh Request dh gS] D;k okLro esa os Elements Database Schema dk fgLlk gSa vFkok ughaA lkFk gh DBMS ;s Hkh Verify djrk gS fd D;k User dks ml tkudkjh dks izkIr djus dk vf/kdkj gS] ftlds fy, mlus Request fd;k gSA



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tc User Database ds fdlh Data dks Modify djuk pkgrk gS] rc Hkh DBMS Data Dictionary esa tkrk gS vkSj mu Integrity Constraints dks Check djrk gS] ftUgsa mu Relation ij Place fd;k x;k gks ldrk gSA ;fn DBMS dk Data ds lkFk Constraint Match gks tkrk gS] vkSj DBMS dks yxrk gS fd User ,d Legal Operation dj jgk gS] rks DBMS ml User dh Request dks iwjk djrk gS vkSj Database ds fdlh Relation ds Data dks Modify djus dh Permission ns nsrk gSA ysfdu ;fn User Data ds lkFk Apply fd, x, Constraint dh t:jr dks iwjk ugha djrk gS] rks DBMS User dks ,d Error Message nsrk gS vkSj Database ds fdlh Hkh Relation ds fdlh Hkh Data esa dksbZ Change ugha djrk gSA D;ksafd Relational Database esa lHkh izdkj ds Data Accesses Data Dictionary ds Through gksrs gSa] blfy, Relational DBMS dks Data Dictionary Driven Hkh dgk tkrk gSA os lHkh Relations tks ,d Data Dictionary dks Create djrs gSa] dqN gn rd DBMS ij fuHkZj gksrs gSaA blfy, fofHkUu izdkj ds DBMS fofHkUu rjhdksa ls bl Data Dictionary dks Manage djrs gSaA

Normalization fofHkUu izdkj ds Entities o muds Attributes dks dbZ rjhdksa ls fdlh Relation ds :i esa Represent fd;k tk ldrk gSA bl v/;k; esa ge Normalization ds Process dks le>saxsA tc ge bl Process ds vk/kkj ij fofHkUu Relations Create djrs gSa] rc ,d [kjkc Database Design ls iSnk gksus okyh fofHkUu izdkj dh leL;k,a Avoid gks tkrh gSaA Database ds Normalization ds nks rjhds izpfyr gSaA igys rjhds esa ,d ER Diagram ds vk/kkj ij Normalization fd;k tkrk gSA bl rjhds esa ;fn ER Diagram dks Correctly Draw fd;k x;k gS] rks ge dqN Simple Rules dks Follow djrs gq, ml ER Diagram dks ,sls Relations esa Translate dj ldrs gSa] tks T;knkrj Relational Design Problems dks Avoid gks tkrk gSA bl Normalization Process dh leL;k ;s gS fd bl rjhds ds vk/kkj ij tks Database Design curk gS] og Design lgh gS ;k ugha] bl ckr dks fuf”pr djus dk dksbZ rjhdk ugha gksrk gSA nwljs rjhds esa ge fofHkUu Relations Create djus ds fy, Theoretical Concept dks Use djrs gSaA ;s rjhdk igys rjhds dh rqyuk esa FkksMk vf/kd tfVy gS] ysfdu blls cuus okyk Design ,d Better Design gksrk gSA Practically bu nksuksa rjhdksa ds Combination dks Use djds] T;knk vklkuh ls ,d vPNk Design Create dj ldrs gSaA lcls igys ge ER Diagram Create djrs gSa vkSj bldk iz;ksx djds Relations Create djrs gSaA mlds ckn nwljs rjhds ds Theoretical Rules dks mu Relations ij Apply djds Design dks Check djrs gSaA

Translating an ER Diagram into Relations ,d ,slk ER Diagram, ftlds lHkh Many To Many Relationships dks Composite Entities dk iz;ksx djds One To Many Relationships esa Convert dj fy;k x;k gks] rks Directly Database Relations esa Translate dj ldrs gSaA ,slk djus ds fy, gesa fuEu Steps dks Follow djus gksrs gSa%



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1 gj Entity ds fy, ,d Table Create djrs gSaA 2 gj og Entity tks fdlh ,d ;k ,d ls T;knk Relationships ds dsoy “One” End dh

rjQ gks vkSj “Many” End dh rjQ uk gks] ,sls Entity dh Table esa dsoy ,d Single-Column Primary Key dks Define djuk gksrk gSA

3 gj og Entity tks fdlh ,d ;k ,d ls vf/kd Relationship ds “Many” End dh rjQ gks] ,sls Entity dh Table esa mlds Parent Table, tks fd “One” End dh rjQ gksrk gS] dh Primary Key dks viuh Table esa Foreign Key dh rjg Use djuk pkfg,A

4 ;fn ,d Entity tks fdlh ,d ;k ,d ls T;knk Relationships ds “Many” End dh rjQ gks vkSj mlesa dksbZ Natural Primary Key gks] tSls fd Invoice Number ;k Order Number, rks bl Single-Column Primary Key dks Use djuk pkfg,A ysfdu ;fn ,slk uk gks] rks bl Table dh Parent Table ds Primary Key dks fdlh vU; Column ;k Columns ds Group ds lkFk Composite Primary Key ds :i esa Use djuk pkfg,A

bu Guidelines dks Follow djds ge “Music Store” Database ds Design dks fuEukuqlkj Theoretically Represent dj ldrs gSa% Customer (CustID, FName, LName, Street, City, State, Pincode, Telephone, CreditCardNo, CardExpiryDate) Item (ItemID, Title, DistID, RetailPrice, ReleaseDate, Genre) Order (OrderID, CustID, OrderDate, OrderFilled) OrderLines (OrderID, ItemID, Quantity, DiscountApplied, SellingPrice, LineCost, Shipped) Distributor (DistID, Name, Street, City, State, Pincode, Telephone, ContactPerson, ContactPersonExt) Actor (ActorID, Name) Performance (ActorID, ItemID, Role) Producer (ProducerID, Studio) Production (ProductionID, ItemID) bu Relations dks FkksMk lk Modify fd;k x;k gS] ysfdu bu Modifications dk ER Diagram ;k Database ds dke djus ds rjhds ij dksbZ vUrj ugha iMk gSA

Normal Forms os Theoretical Rules ftudk fdlh Hkh Relational Database Design ds Compatible gksuk t:jh gksrk gS] Normal Forms dgykrs gSaA gj Normal Forms dqN Strict Rules dk lewg gksrk gSA Theoretically Database ftrus Higher Form esa gksrk gS] Relations ds chp dk Design mruk gh vPNk gksrk gSA



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tSlkfd ge fiNys fp= esa ns[kdj le> ldrs gSa] fdlh Hkh Design dh 6 Normal Forms gks ldrh gSaA ;s fp= bl ckr dks n”kkZrk gS fd ;fn dksbZ Design fdlh Higher Form esa gS rks og Design mldh lHkh Inner Normal Form esa t:j gksrk gSA ;kuh ;fn dksbZ Design Inner Normal Form esa ugha gks rks mls Higher Normal Form esa Define ugha fd;k tk ldrk gSA T;knkrj Cases esa ;fn ge gekjs Relations ;k Tables Third Normal Form (3NF) rd Hkh Normalize dj ysrs gSa] rks ge [kjkc Database Design ds T;knkrj Problems dks Solve dj pqds gksrs gSaA ;kuh fdlh Database dh lHkh Tables dks 3rd Normal Form rd Normalize dj ysus ij ml Database dh Design lEcaf/kr T;knkrj ijs”kkfu;ka lekIr gks tkrh gSaA Boyce-Codd (BCNF) o 4th Normal Form dks fo”ks’k Situations dks Handle djus ds fy, dHkh&dHkkj gh Database ij Apply fd;k tkrk gSA gkykafd bu nksuksa Normalization Processes dks Hkh Conceptually le>uk ljy gksrk gS vkSj t:jr iMus ij bUgsa Practice esa Hkh fy;k tk ldrk gSA Fifth Normal Form ds fu;e cgqr gh Complex gksrs gSa vkSj bUgsa Practically Use djuk dkQh eqf”dy gksrk gSA dksbZ Relation 5th Normal Form esa gS ;k ugha] bl ckr dks Verify djuk dkQh eqf”dy gksrk gSA T;knkrj Database Designers 5th Normal Form rd fdlh Hkh Relation dks Normalize ugha djrs gSaA ;fn mUgsa yxrk gS fd mudk Relation 3rd Normal Form ;k t:jr ds vk/kkj ij 4th Normal Form esa gS] rks os ;s eku ysrs gSa fd mudk Design Generally Problem Free gSA fp= esa n”kkZ, x, 6 Normal Forms ds vykok ,d vkSj Normal Form gksrk gS] ftls Domain/Key Normal Form dgk tkrk gSA ;s ,d iwjh rjg ls Theoretical Concept gksrk gS vkSj vkt ds le; esa bl Normal Form dks fdlh Hkh Practical Design esa Use ugha fd;k tkrk gSA



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First Normal Form ;fn fdlh Table ds lkjs Data ,d 2-Dimensional Table ds :i esa gSa vkSj muesa ls fdlh Hkh Data ds Group dk Repetition ugha gks jgk gS] rks ml Table dks 1st Normal Form esa ekuk ldrs gSA 1st Normal Form dks le>us dk eq[; vk/kkj ;s gS fd ge Data ds Repeating Group dh izd`fr dks le>saA fdlh Relation dk ,d ,slk Attribute, ftlesa ,d ls T;knk Data Store gks ldrs gksa] dks Repeating Group Data dgk tkrk gSA tc ge fdlh Repeating Group Data dks ER Diagram esa Represent djuk pkgrs gSa] rc ge ml Repeating Group Data dks Multi-Valued Attribute ds :i esa Represent djrs gSaA mnkgj.k ds fy, ekuyks fd ge fdlh Employee ds Relation ds lkFk izfØ;k dj jgs gSa vkSj gesa fdlh Employee ds cPpksa ds uke o Birth Date dks Employee ds Relation esa Data ds :i esa Store djuk gSA vc pwafd ,d Employee ds ,d ls T;knk cPps Hkh gks ldrs gSa] blfy, ,d gh Employee dks Represent djus okys ,d gh Row ds Child Name Filed o Child Birth Date Field esa ,d ls T;knk ekuksa dks Store djus dh t:jr iM ldrh gS] tcfd fdlh Hkh Relational Database esa fdlh ,d Row ds ,d Field esa dsoy ,d gh eku dks Store fd;k tk ldrk gSA bl fLFkfr esa Child dk uke o Birth Date Employee ds Record esa ,d ls T;knk ckj Repeat gks ldrs gSa] blfy, bu nksuksa Data dks Employee ds Relation ds fy, Repeating Group of Data dgk tk ldrk gSA bl ckr dks ge ,d lkj.kh }kjk fuEukuqlkj n”kkZ ldrs gSa% EmpID FName LName DOB ChildName ChildBirthDate 001 Rahul Sharma 10/12/1982 Rohit Sharma 15/12/2006 Mohit Sharma 20/10/2008 bl Table esa ge ns[k ldrs gSa fd Rahul uke ds ,d Employee ds nks cPps Rohit o Mohit gSa] ysfdu ge nksuksa cPpksa ds Data dks Employee ds Relation esa Store ugha dj ldrs gSa] D;ksafd ;fn ge ,slk djus dh dksf”k”k djrs gSa] rks gesa ,d gh Attribute Column esa ,d ls T;knk ukeksa o Birthdates dks Store djuk gksxk] tks fd ,d Relational Database esa lEHko ugha gSA fdlh Relational Database esa Repeating Groups dks Allow uk djus dk ,d vPNk dkj.k Hkh gSA bl dkj.k dks le>us ds fy, ge ,d mnkgj.k ns[krs gSa] ftlesa ,d Table esa fuEukuqlkj dqN Employees o muds cPpksa ds uke Stored gSa%



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bl Table esa ge ns[k ldrs gSa fd ,d gh Single Row ds Children Name Field o Children Birthdates Field nksuksa gh Fields esa ,d ls T;knk eku Stored gSaA ;s O;oLFkk nks cMh Problems Create djrh gS%

1 bl Table esa ,slk dksbZ rjhdk ugha gS] ftlls ;s tkuk tk lds fd fdl Child dk Birth Date D;k gSA bl O;oLFkk dks Use djus ij gesa gesa”kk Children ds uke o Birth Date nksuksa dks leku Øe esa Store djuk t:jh gksrk gSA fdlh Table esa Children Name Field esa ftl cPps dk uke igys fy[kk x;k gS] gesa mlh cPps dk Birth Date igys fy[kuk gksrk gS vkSj ,slk dksbZ fuf”pr rjhdk ugha gksrk gS] ftlls ;s Verify gks lds fd geus ftl cPps dk uke igys fy[kk gS] ge mlh cPps dh Date Of Birth Hkh igys gh fy[k jgs gSa ;k ughaA

2 tc ge fdlh Table esa Multi-Valued Data Store djrs gSa] rc DBMS fdlh Data

dks Search djus ds fy, ml Multi-Valued Column dks Extract djrk gS vkSj ml Column ij Sequential Processing dks Apply djds Required Data dks izkIr djrk gS] tks fd lcls /kheh Searching Process gksrh gSA

bu nksuksa leL;kvksa dk ,d gh Solution gS fd fdlh Hkh Single Column esa Multiple Values dks Store uk fd;k tk, ;kuh Repeating Group of Data dks fdlh Hkh Relation esa Avoid fd;k tk,A Repeating Groups dh leL;k ls cpus vkSj Relation dks First Normal Form esa ykus ds nks rjhds gSaA igyk rjhdk ,d lgh rjhdk gS tcfd nwljk rjhdk ,d xyr rjhdk gSA ge igys xyr rjhds dks ns[ksaxs rkfd ge ;s le> ldsa fd gesa ,d Database esa D;k ugha djuk pkfg,A bl xyr rjhds dks ge fuEu lkj.kh }kjk le> ldrs gSa] ftlesa fdlh Repeating Group ds Data dh fofHkUu Values dks Handle djus ds fy, Relation esa Columns dh la[;k dks Increase dj fy;k tkrk gS%

bl Example esa fdlh Employee ds rhu Childs ds uke o Birth Dates dks Store fd;k tk ldrk gSA ;s Table First Normal Form ds Criteria ls esy ugha dj jgk gSA gkykafd bl Table esa Data ds Repeating Groups ugha gSa vkSj gj Child dh Birth Date dks vyx Store fd;k x;k gSA fQj Hkh bl Design esa dbZ Problems gSa] tks fuEukuqlkj gSa%

1 bl Relation esa ge flQZ rhu Child ds gh Name o Birth Date dks Store dj ldrs gSaA blfy, ;fn ge Jane Smith ds pkSFks cPps dk uke o Date Of Birth Store djuk pkgsa] rks bl Relation esa ml Child ds fy, dksbZ txg ugha gSA ;fn ge pkSFks cPps dk Hkh Data blh Relation esa Store djuk pkgsa] rks ;k rks gesa ,d vkSj Field Pair Create djuk gksxk ;k fQj ,d vkSj Row esa bl Data dks Store djuk gksxkA ;fn ge pkSFks cPps ds Data dks ,d vkSj Row esa Store djrs gSa] rks fQj ml cPps dks mlds Father ds EmpID ls Relate djus ds fy, gesa EmpID ds lkFk de ls de



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,d Child ds uke ds Column dks Hkh feykuk gksxkA ;kuh gesa Composite Key dk iz;ksx djuk gksxkA

2 ;fn ge bl rjhds dks Use djrs gSa] rks ftu Employees ds ,d ;k nks gh Child gSa]

muds Row esa rhljs Child ds Data dh txg Empty jgsxh] ftlls Employee ds Record }kjk Reserved Space Waste gksxkA

3 bl rjhds dks Use djus ij fdlh Particular Child dh Searching djuk dkQh

eqf”dy gks tkrk gSA bl Design esa ;fn DBMS ls ;s iwNk tk,] fd “D;k bl Relation esa Lee uke dk dksbZ Child gS ;k ugha\” rks DBMS dks ,d Query Construct djuk iMrk gS] ftlesa rhuksa Childs ds uke Included gksrs gSa] D;ksafd DBMS ds ikl ,slk dksbZ rjhdk ugha gksrk gS] ftlls og Particular “Lee” ds gh Column dks Identify dj ldsA

Repeating Group dks Handle djus dk lgh rjhdk ;s gS fd Repeating Group ds Data dks Store djus ds fy, ,d vkSj Entity ;kuh Table Create fd;k tk,] tks Repeating Group ds Multiple Records ;k Instances dks Handle dj ldsA ;fn ge gekjs bl mnkgj.k ds lUnHkZ esa ns[ksa] rks gesa Children uke dh ,d vkSj Table dks Create djuk gksxk] ftlesa fuEukuqlkj Data Store fd, tk ldrs gSa% Employees EmpID FirstName LastName 1001 Jane Doe 1002 John Doe 1003 Jane Smith 1004 John Smith 1005 Jane Jones Employees EmpID ChildName BirthDate 1001 Mary 1/1/92 1001 Sam 5/15/94 1002 Mary 1/1/92 1002 Sam 5/15/94 1003 John 10/5/94 1003 Pat 10/12/90 1003 Lee 6/6/96 1003 Mary 8/21/94 1004 Michael 7/4/96 1005 Edward 10/21/95 1005 Martha 10/15/89 ge ns[k ldrs gSa fd vc nksuksa gh Tables esa dksbZ Hkh Repeating Group Of Data ugha gS blfy, bl Design ls igys crkbZ xbZ lHkh izdkj dh leL;k,a lekIr gks tkrh gSaA ;kuh bl Design ls gesa mijksDr lHkh Problems dk fuEukuqlkj Solution izkIr gks tkrk gS%



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• bl Design esa ge fdlh Employee ds lHkh Childs ds Name o Birth Dates dks Store dj ldrs gSa] D;ksafd ;gka ij Store fd, tkus okys Children ij fdlh izdkj dh dksbZ Limitation ugha gSA

• bl Design esa mruk gh Space Use gksrk gS] ftrus dh t:jr fofHkUu Childs ds Data dks Store djus ds fy, gksrh gS] blfy, Storage Space Waste ugha gksrk gSA

• bl Design esa fdlh Child dh Searching djuk dkQh ljy gks tkrk gS] D;ksafd Child dk uke dsoy ,d gh Column esa Store gks ldrk gS] blfy, DBMS dks fdlh Hkh Child dk uke Search djus ds fy, dsoy ,d gh Column dks /;ku esa j[kuk gksrk gSA

gkykafd First Normal Form ds Relations esa Data ds Repeating Groups ugha gksrs gSa] ysfdu muesa vU; izdkj dh dbZ vkSj Problems gksrh gSaA First Normal Form ds Relation dh leL;kvksa dks le>us ds fy, ge Music Store Database ds Data Entry Form ls Connected Back-End Table dks gh mnkgj.k ds :i esa ys jgs gSa] ftlesa Data Entry Form ls Enter fd;k x;k Data tkdj Store gksrk gSA Music Store Data Entry Form ls Connected Back-End Relation ds Notation dks ge fuEukuqlkj Represent dj ldrs gSa% Orders (CustID, FName, LName, Street, City, State, Pincode, Telephone, OrderDate, ItemID, Title, Price, HasShipped) bl Table esa gesa tks lcls igys dke ds :i esa Primary Key dks Determine djuk gksrk gSA bl Table esa dsoy Customer Number ls fdlh Order dks iwjh rjg ls Uniquely Identify ugha fd;k tk ldrk gS] D;ksafd gj Item ds Order ds lkFk gh CustID Repeat gksrk gSA blh rjg ls dsoy ItemID dks Primary Key ds :i esa Use ugha fd;k tk ldrk gS] D;ksafd gj Order ds lkFk ;s Hkh Repeat gksrk gSA bl Relation esa Primary Key dk dsoy ,d gh mfpr rjhdk gks ldrk gS vkSj og rjhdk Composite Key dk gSA bl mnkgj.k esa ge OrderID o ItemID nksuksa ds Combination dks Primary Key ds :i esa Use dj ldrs gSaA ;fn ge OrderID o ItemID ds Combination dks Primary Key ds :i esa Use djrs gSa] rks bl Relation esa ge nks cgqr gh egRoiw.kZ dkeksa dks iwjk ugha dj ldrs gSa] ftUgsa fuEukuqlkj crk;k x;k gS%

1 ge rc rd fdlh Customer ds Data dks Relation esa Store ugha dj ldrs gSa] tc rd fd og Customer de ls de ,d Order Place uk djs] D;ksafd fcuk ,d Order vkSj ml Order ij fLFkr ,d Item ds] gekjs ikl ,d Complete Primary Key ugha gksrh gSA

2 blh rjg ls ge rc rd fdlh Item dh Information dks Hkh Relation esa Store ugha

dj ldrs gSa] tc rd fd dksbZ Customer fdlh Order }kjk ml Item dks Order uk djs] D;ksafd fcuk OrderID ds Hkh ,d Complete Primary Key ugha cu ldrkA

;s nksuksa dkj.k Insertion Anomalies gSa] tks ,d ,slh Situation dks Represent dj jgs gSa] ftlesa ge fdlh Relation esa blfy, fdlh Data dks Insert ugha dj ldrs gSa] D;ksafd gekjs ikl ,d Complete Primary Key ugha gSA



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dksbZ Hkh Relation, tks fd First Normal Form esa gksrk gS] mlesa Insertion Anomalies dh fLFkfr Common :i ls gksrh gh gSA Insertion Anomalies dh fLFkfr rc iSnk gksrh gS] tc fdlh ,d Relation esa ,d ls T;knk Entities ds Data dks Store djus dh dksf”k”k dh tkrh gSA bl Situation esa Anomaly gesa ml le; ,d Unrelated Entity tSls fd Item ds Data dks Insert djus ds fy, etcwj djrk gS] tc ge fdlh nwljs Entity tSls fd Customer ds Data dks Insert dj jgs gksrs gSaA First Normal Form ds Relations ml le; Hkh leL;k,a iSnk djrs gSa] tc ge ml Relation ls fdlh Data dks Delete djus dh dksf”k”k djrs gSaA mnkgj.k ds fy, ekuyks fd ge ml Customer ds Order dks Delete djuk pkgrs gSa] ftlus vius Single Item dk Order Cancel dj fn;k gSA vc ;fn

1 Customer us igyh gh ckj Order fn;k gks vkSj dsoy ,d gh Item dk Order fn;k gks] rks ml Customer ds Order dks Delete djus ij ml Customer dh Information Hkh Music Store ds Database ls Permanently Delete gks tk,xh] ftlls Music Store Organization dk ml Customer ls rc rd ds fy, Permanently Link VwV tk,xk] tc rd fd og nqckjk dksbZ Order ugha nsrk gSA

2 Customer us igyh gh ckj ml Item dk Order fn;k gks vkSj ml Customer ls

igys fdlh nwljs Customer us ml Item dk Order ugha fn;k gks] rks ml Order dks Delete djus ij ml Item dh Information Hkh Music Store ds Database ls Permanently Delete gks tk,xhA

3 Customer us vius Order esa dsoy ,d gh Item dk Order fn;k gks] rks Order dks

Delete djus ij ml Order dh iwjh Information Database ls Delete gks tk,xhA ;s Deletion Anomalies blfy, iSnk gksrh gSa] D;ksafd fdlh Row dh Primary Key ds ,d Part esa ml le; Null Store gks tkrk gS] tc Item ds Data dks Delete djrs le; gesa Data dh iwjh Row dks Delete djuk iMrk gSA Deletion Anomaly dk ifj.kke ;s gksrk gS fd Music Store Database ls os Data Hkh Delete gks tkrs gSa] ftUgsa ge Database esa Stored j[kuk pkgrs gSaA ;fn ge Practical :i ls ns[ksa rks tc gesa fdlh vokafNr Entity ds Data dks Delete djuk gksrk gS] rc bl Anomaly dh otg ls gesa ml Entity ds Data dks Hkh Delete djuk iMrk gS] tks fd Same Table esa rks gksrs gSa ysfdu vokafNr Entity ls Unrelated gksrs gSaA bl iwjs Discussion dk lkjka”k ;s gS fd ,d gh Table esa ,d ls T;knk Entities ds Data dks Store ugha djuk pkfg,A Orders ds Relation esa ,d vfUre Anomaly Update/Modification Anomaly Hkh gSA Orders Relation esa gj Order ds lkFk gj Customer dh Information dks ckj&ckj Store djus dh otg ls Music Store Database esa ,d gh Customer ds cgqr lkjs Unnecessary Duplicated Data Store gks tkrs gSaA blfy, tc ,d Customer Move gksrk gS] rc ml Customer us ftrus Hkh Items ds ftrus Hkh Orders Music Store Organization dks fn, gksrs gSa] Database esa mu lHkh Items ds Orders dh Row dks Modify djds Customer ds Data dks Change djuk iMrk gS] D;ksafd gj Item dh Entry Database esa djus ds fy, ml Item dh Information ds lkFk Customer dh Information dks Hkh Database esa Store fd;k tkrk gSA



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vc ;fn gj Row dks Correctly Change uk fd;k tk,] rks fdlh Particular Customer dh Information dks Represent djus okys ftu lHkh Data dks gesa”kk leku gksuk pkfg,] os leku ugha jg tkrs gSaA Data dh bl Inconsistency dh lEHkkouk ds dkj.k Modification Anomaly dh Situation iSnk gksrh gSA

Second Normal Form First Normal Form dh fofHkUu Anomalies dks gVkus dk lek/kku ;s gS fd First Normal Form okyh Relation ls lHkh Entities dks ,d vyx Relation ds :i esa Define fd;k tk,A mnkgj.k ds fy, Music Store ds bl Orders Relation esa ls ge pkj Lora= Entities (Customers, Items, Orders o Line Items ) dks vyx dj ldrs gSaA ,slk djus ij Music Store Organization dk ;s Relation Second Normal Form esa vk tkrk gSA Theoretical “kCnksa esa Second Normal Form dks fuEukuqlkj ifjHkkf’kr fd;k tk ldrk gS% tc Relation First Normal Form esa gks vkSj lHkh Non-Key Attributes, Functionally flQZ Primary Key ij Dependent gksA ;fn dksbZ Non-Key Attribute Functionally dsoy Primary Key ij Depend uk gksdj fdlh Non-Key Attribute ij Depend gks] rks ml Non-Key Attribute vkSj ml ij Depend lHkh vU; Non-Key Attributes dks ml Relation ls gVkdj ,d u, Relation esa Define djuk pkfg, vkSj bl u, Relation esa ml Key dks Primary Key cuk nsuk pkfg,] ftl ij vU; Attributes Depend gksaA Functional Dependency nks Attributes ds chp dh ,d One-Way Relationship gksrh gSA tSls fdlh Relation esa fdlh Hkh le; ,d Attribute A ls fdlh nwljs Attribute B dh dsoy ,d gh Value Associated gksuh pkfg,A mnkgj.k ds fy, ekuyks fd Orders Relation esa A ,d Customer dk Customer Number ;k CustID gSA vc gj Customer dk Customer Number ,d First Name, ,d Last Name, ,d Street Address, ,d City, ,d State, ,d Pincode o ,d Telephone Number ls Associated gksrk gSA gkykafd bu Attributes dh Values dks fdlh Hkh le; Change fd;k tk ldrk gS] ysfdu fdlh Hkh le; gj Attribute esa dsoy ,d gh eku gksrk gSA bl fLFkfr esa ge dg ldrs gSa fd First Name, Last Name, Street Address, City State, Pincode o Telephone Numbers ;s lHkh Functionally Customer Number ij Dependent gSaA Attributes ds chp dh bl Relationship dks vDlj fuEukuqlkj Represent fd;k tkrk gS% CustID -> FName, LName, Street Address, City, State, Pincode, Telephone vkSj bls bl rjg Read fd;k tkrk gS fd “Customer Number Determines First Name, Last Name, Street Address, City State, Pincode and Telephone Numbers”. bl Relationship esa Customer Number ;kuh CustID dks Determinant ds :i ds tkuk tkrk gS] tks fd ,d ,slk Attribute gksrk gS] tks vU; Attributes dh Values dks Determine djrk gSA /;ku j[ksa fd Functional Dependency dks Reverse Direction esa Represent ugha fd;k tk ldrk gSA mnkgj.k ds fy, fdlh Hkh First Name ;k Last Name dks ,d ls T;knk



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Customer Numbers ds lkFk Associate fd;k tk ldrk gSA Orders Table esa fuEu Functional Dependencies gSa% CustID -> FName, LName, Street Address, City, State, Pincode, Telephone ItemID -> Title, Price OrderID-> CustID, OrderDate ItemID + OrderID -> HasShipped /;ku nsa fd Relation esa gj Entity ds fy, ,d Determinant gS vkSj Determinant ogh gS] ftls geus Entity Identifier ds :i esa Choose fd;k gSA tc fdlh Entity esa Composite Identifier gksrk gS] rc Determinate Hkh Composite gksrk gS] tSlkfd pkSFks Representation esa ItemID+OrderID dk Group ,d Composite Identifier gSA bl Example esa dksbZ Order Ship fd;k tk pqdk gS vFkok ugha] ;s ItemID o OrderID ds Combination ij Depend djrk gSA tc ge fdlh Database Environment esa fdlh Relation ds fofHkUu Attributes ds chp dh Functional Dependencies dks Correctly Identify dj ysrs gSa] mlds ckn ge budk iz;ksx Relations dks Second Normal Form esa Transform djus ds fy, dj ldrs gSaA bl fLFkfr esa gj Determinant Relation dk Primary Key cu tkrk gS vkSj ftrus Hkh Attributes bl Determinant ij Depend gksrs gSa] os lHkh Attributes Relation ds Non-Key Attributes cu tkrs gSaA bl Concept ds vk/kkj ij Music Store Organization ds Original Relation esa ls ftu pkj Entities dks Lora= :i ls Identify djds vyx fd;k tkrk gS] mUgsa fuEukuqlkj Represent fd;k tk ldrk gS% Customer (CustID, FName, LName, Street Address, City, State, Pincode, Telephone) Items (ItemID, Title, Price) Orders (OrderID, CustID, OrderDate) LineItems (ItemID, OrderID, HasShipped ) ;s pkjksa gh Relations ER Diagram ds ,d Single Entity ls lEcaf/kr gksrs gSaA /;ku nsa fd Database Design dks Functional Dependencies o Entities nksuksa esa ls fdlds vk/kkj ij Derive fd;k tk,] bldk dksbZ fuf”pr fu;e ugha gksrk gSA egRoiw.kZ ckr ;s gksrh gS fd ER Diagram o vius Relation esa Identify dh xbZ Functions Dependency nksuksa ds chp Consistency gksuh pkfg,A bl ckr ls Database ds Design ij dksbZ izHkko ugha iMrk gS fd ge vius Relation dks Functional Dependency ds vk/kkj ij Design djrs gSa ;k Entities ds vk/kkj ijA T;knkrj fLFkfr;ksa esa Database Design ,d Interactive Process gksrk gS] ftlesa ge Database dk Initial Design Create djrs gSa] mls Check djrs gSa] Modify djrs gSa vkSj fQj ls Check djrs gSaA ge Design Process ds fdlh Hkh Stage esa Function Dependency vkSj@;k Entities dks ns[k ldrs gSa vkSj ,d nwljs ds Against Check dj ldrs gSaA D;ksafd gesa”kk ;s t:jh ugha gksrk gS fd geus ftl Relation dks First Normal Form esa eku fy;k gS] og okLro esa First Normal Form esa gksA Design Process ds fdlh Hkh Stage esa gesa ,slk eglwl gks ldrk gS] fd Relation iwjh rjg ls First Normal Form esa ugha gS vkSj mls fQj ls First Normal Form esa ykus dh t:jr gSA tc ge Relation ij Second Normal



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Form ds Criteria Rules dks Apply djrs gSa] rc Original Relation esa Present Anomalies Eliminate gks tkrh gSa vkSj ge fuEu dke dj ldrs gSa%

1 Customer ds Order Place djus ls igys gh ge ml Customer ds Data dks Database Relation esa Store dj ldrs gSaA

2 ge fdlh Order ds Data dks fcuk Items dh Information ds Hkh Database Relation esa Store dj ldrs gSaA

3 fdlh Customer }kjk fdlh Particular Item dk Order fn, tkus ls igys Hkh ge Item ds Data dks Database Relation esa Store dj ldrs gSaA

4 vc Line Items dks fdlh Hkh Order ls Delete fd;k tk ldrk gSA ,slk djus ij Item dks Describe djus okys Data, Lo;a Order ;k fdlh Item dh Information ij bldk dksbZ izHkko ugha iMrk gSA

5 Customer ls lEcaf/kr Data dks dsoy ,d gh ckj Store fd;k tkrk gS] blfy, ;fn Customer ds Data esa fdlh izdkj dk Change djuk iMs] rks ;s Change dsoy ,d gh ckj djuk iMrk gSA blesa Modification Anomaly dk izHkko ugha iMrk gS] D;ksafd Customer ds Data dks Database Relation esa dbZ ckj Store ugha fd;k tkrk gSA

gkykafd Second Normal Form fofHkUu Relations esa ls T;knkrj leL;kvksa dks lekIr dj nsrk gSA cgqr de ckj gh ,slh fLFkfr;ka gksrh gSa] tc gekjk Relation Second Normal Form esa gksrk gS] fQj Hkh mlesa Anomalies gksrh gSA mnkgj.k ds ekuyks fd Music Store ftu Distributors ls Titles ysrk gS] mu lHkh Distributors ds ikl dsoy ,d gh Store Room gS] tgka ij flQZ ,d Telephone gSA bl fLFkfr esa fuEu Relation Second Form esa gksxk% Items (ItemID, Title, Distributor, WareHousePhoneNo) gj ItemID ds fy, bl Relation esa dsoy ,d Title, ,d Distributor o ,d Warehouse Telephone Number gSA blfy, bl Relation esa ,d Insertion Anomaly gSA ge rc rd fdlh Distributor dk Data Music Store Database esa Store ugha dj ldrs gSa] tc rd fd gesa ml Distributor ls dksbZ Item izkIr ugha gksrk gSA lkFk gh bl Relation esa ,d Deletion Anomaly Hkh gS] D;ksafd ;fn ge fdlh Distributor }kjk Hksts x, Only Item dh Details dks Delete dj nsrs gSa] rks ge Distributor dh Information dks Hkh [kks nsaxsA bl Relation esa gj Item ds Record ds lkFk Distributor ds Warehouse ds Phone Number dks Hkh Store fd;k tkrk gS] ftlls bldk ckj&ckj Duplication Hkh gksrk gS] blfy, bl Relation esa Modification Anomaly Hkh gSA bl fLFkfr esa ;s Relation Second Normal Form esa rks gS] ysfdu Third Normal Form esa ugha gSSA

Third Normal Form fdlh Relation dks Third Normal Form ds vk/kkj ij blfy, Normalize fd;k tkrk gS] rkfd mij crkbZ xbZ Anomalies dk lek/kku gks ldsA ;fn ge Entities ds vk/kkj ij ns[ksa] rks Items Relation esa Item o Distributor nks Entities ls Related Data Store gks jgs gSaA



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blfy, mijksDr Anomalies dks gVkus ds fy, gesa bl Relation dks fuEukuqlkj nks Individual Relations esa Divide djuk gksxk% Items (ItemID, Distributor) Distributors (DistID, WareHousePhoneNo) Third Normal Form dk Theoretical Definition ;s gS fd dksbZ Relation rc Third Normal Form esa gksrk gS] tc ml Relation esa dksbZ Transitive Dependencies ugha gksrh gSaA Original Relation esa geus ftl Functional Dependencies ds ckjs esa tkuk Fkk] mls gh Transitive Dependency dgrs gSaA ,d Relation esa Transit Dependency rc Exist gksrh gS] tc gekjs lkeus fuEukuqlkj Functional Dependency gksrh gS% A -> B and B -> C So Indirectly A -> C ;gh Dependency Original Items Relation esa gSA Warehouse ds Phone Number dk Functionally Item Number ij Depend gksus dk Only dkj.k ;gh gS fd Distributor Functionally Item Number ij Dependent gS vkSj Phone Number Functionally Distributor ij Dependent gSA blfy, okLrfod Functional Dependency fuEukuqlkj gS% ItemID -> Distributor Distributor -> WareHousePhoneNo tcfd WareHousePhoneNo Indirectly ItemID ij Dependent gS] ftls ge Transitive Dependency dgrs gSaA Transitive Dependency dks ;fn ge Mathematical Example ds :i esa Represent djsa] rks ;fn A Directly cMk gks B ls vkSj B Directly cMk gks C ls rks A Indirectly C ls Hkh cMk gksrk gSA gekjs Original Items Relation esa nks Determinants gSa vkSj nksuksa gh Determinants dks muds Relation dk Primary Key gksuk pkfg,] D;ksafd gj Determinate gesa”kk vius Relation dk Primary Key gh gksrk gSA gkykafd bl Relation esa Second Determinate dk ,d Attribute ds :i esa Exist gksuk gh Transitive Dependency dk dkj.k ugha gSA cfYd okLro esa Transitive Dependency dk eq[; dkj.k ;s gS fd nwljk Determinant Relation dk Candidate Key ugha gSA bls le>us ds fy, fuEu Relation dk mnkgj.k ns[krs gSa% Items (ItemID, UpcCode, Distributor, Price) ItemID og Number gS] ftls Music Store Organization vius gj Item dks Uniquely Identify djus ds fy, Use djrk gS] tcfd UPC Code og Industry-Wide Code gS] ftls gj Item dks Uniquely Identify djus ds fy, Use fd;k tkrk gSA vc bl Relation esa Functional Dependencies fuEukuqlkj gSa% ItemID -> UpcCode, Distributor, Price UpcCode -> ItemID, Distributor, Price D;k bl Relation esa vc Transitive Dependency gSA ugha] vc bu Relations esa Transitive Dependencies ugha gSa] D;ksafd Second Determinant ,d Candidate Key gSA D;ksafd



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“Music Store” UpcCode dks Hkh mruh gh vklkuh ls fdlh Item dks Uniquely Identify djus ds fy, Use dj ldrk gS] ftruh vklkuh ls og Primary Key dks Use djrk gSA bl Relation esa vc fdlh izdkj dk dksbZ Insertion, Deletion ;k Modification Anomaly ugha gS vkSj ;s Relation vc dsoy ,d Item Entity dks gh Describe dj jgk gSA Transitive Dependency fdlh Relation esa rc Exist gksrh gS] tc dksbZ Determinant] tks fd Relation ds fy, Primary Key ugha gksrk gS og ml Relation dk Candidate Key Hkh ugha gksrk gSA mnkgj.k ds fy, ge ftl Items Table dks mnkgj.k ds :i esa mi;ksx esa ys jgs gSa] mlesa Distributor ,d Determinant gS ysfdu og Distributor ml Items Table ds fy, Candidate Key ugha gSA D;ksafd ,d Distributor ls ,d ls T;knk Items Music Store esa vk jgs gSaA tc Second Normal Form ds Relation esa dksbZ Transitive Dependency gksrh gS] rc gesa ml Relation dks nks NksVs&NksVs Relations esa Divide dj ysuk pkfg, vkSj nksuksa Relations esa nksuksa Determinants dks Primary Key cuk ysuk pkfg,A ftl Attributes dks Determinants }kjk Determine fd;k tkrk gS] mu Non-Key Attributes dks muds Determinant ds Relation esa Specify dj nsuk pkfg,A blls Transitive Dependency Remove gks tkrh gS vkSj blls Associated Anomalies Hkh Remove gks tkrh gSa] lkFk gh gekjk Relation Third Normal Form esa vk tkrk gSA ;fn fdlh Second Normal Form ds Relation esa dksbZ Transitive Dependency uk gks] rks og Relation Automatically Third Normal Form esa vk tkrk gSA

Boyce-Codd Normal Form T;knkrj Relations ds fy, Third Normal Form rd Normalized Relation ,d vPNk Design Objective gksrk gSA bl fLFkfr ds Relations T;knkrj Anomalies ls Free gksrs gSaA fQj Hkh ifjfLFkfro”k dbZ ckj Third Normal Form ds Relations esa Hkh FkksMh vyx fdLe dh Anomalies gksrh gSaA bu Anomalies dks BCNF o Forth Normal Form ds Normalization ds vk/kkj ij Handle fd;k tkrk gSA ;fn gekjk Relation Third Normal Form esa gks vkSj mlesa dksbZ Extra Ordinary izdkj dh leL;k uk gks] rks gekjk Relation Automatically BCNF o Fourth Normal Form esa gksrk gSA BCNF dh izfØ;k dks le>us ds fy, ge ,d mnkgj.k ys jgs gSaA ekuyks fd Music Store Organization ;s r; djrk gS fd og vius Database esa ,d vkSj Relation Add djsxk] ftls og vius Music Store ds Employee ds dke djus ds le; dks Schedule djus ds fy, Use djsxkA gj Employee gj jkst 4-Hours dh ,d ;k nks Shift esa dke djsxk vkSj gj Shift esa ,d Employee dks Music Store ds fdlh ,d Station ¼;kuh Stock Room esa Stock dks Manage djus ds fy, ;k fQj Desk ds lkeus Customer dks Handle djus ds fy,½ ij dke djsxk] tcfd ,d Station ij ,d Shift esa flQZ ,d gh Employee dke djsxkA vc Schedule dks Handle djus ds fy, fuEukuqlkj ,d Relation Design fd;k tk ldrk gS% Schedule (EmpID, Date, Shift, Station, WorkedShift?)



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fn, x, Business Rule ds fglkc ls ,d Employee ,d Shift esa ,d Station ij dke djsxk] blfy, bl Relation esa nks lEHkkfor Primary Keys EmpID + Date + Shift ;k Date + Shift + Station gks ldrh gSaA bl fLFkfr esa Functional Dependency dk Relation fuEukuqlkj cusxk% EmpID + Date + Shift -> Station, WorkedShift? Date + Shift + Station -> EmpID, WorkedShift? ,d ckr /;ku esa j[ksa fd ;s Functional Dependency Relation mlh fLFkfr esa lgh gSa] tc gj Station ij gj Shift esa dsoy ,d gh Employee dke djrk gSA ;s Schedule Relation Composite Candidate Keys dks Show dj jgk gSA D;ksafd nksuksa gh Candidate Keys esa Date o Shift Common gSaA Boyce-Codd Normal Form dks fdlh Relation esa Exist blh rjg dh Characteristics dks Handle djus ds fy, cuk;k x;k gSA BCNF Form esa gksus ds fy, fdlh Hkh Relation ij bl fu;e dk Apply gksuk t:jh gksrk gS fd Relation Third Normal Form esa gks vkSj Relation ds lHkh Determinants Candidate Keys gksa] rks Relation BCNF Form esa gksrk gSA

Forth Normal Form BCNF dh rjg gh Forth Normal Form dks Hkh fdlh Relation dh ,d Special Characteristic dks Handle djus ds fy, Design fd;k x;k gS] tks fd cgqr gh de ifjfLFkfr;ksa esa Generate gksrh gSA bl fLFkfr esa tks Special Characteristics gksrh gS] mls lkekU;r;k Multi-Valued Dependency dgk tkrk gSA mnkgj.k ds fy, fuEu Relation dks nsf[k,% MovieInfo (Title, Star, Producer) fdlh Specify dh xbZ Movie esa ,d ls T;knk Stars gks ldrs gSa vkSj mlh Movie dks ,d ls T;knk Producers us Produce fd;k gks ldrk gSA Same Stars ,d ls T;knk Movie esa Appear gks ldrs gSa vkSj Producer Hkh ,d ls T;knk Movies esa Involved gks ldrk gSA blfy, bl Relation ds lHkh Columns dks Composite Primary Key ds :i esa Use djuk t:jh gks tkrk gSA bl mnkgj.k dks ge fuEu lkj.kh esa ns[k ldrs gSa% MovieInfo Table

Title Star Producer Great Film Lovely Lady Money Bags Great Film Handsome Man Money Bags Great Film Lovely Lady Helen Pursestrings Great Film Handsome Man Helen Pursestrings Boring Movie Lovely Lady Helen Pursestrings Boring Movie Precocious Child Helen Pursestrings

pwafd bl Relation esa dksbZ Hkh Non-Key Attribute ugha gS] blfy, ;s Relation BCNF Normalization Form esa gSA fQj Hkh ;s Relation fuEu Anomalies Show djrk gS%

1 ge de ls de ,d Producer dks tkus fcuk fdlh Movie ds Stars dks Insert ugha dj ldrs gSaA



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2 ge de ls de ,d Star dks tkus fcuk fdlh Movie ds Producer dks Insert ugha dj ldrs gSaA

3 ;fn ge fdlh Only Producer dh Information dks Delete djrs gSa] rks ge ml Movie ds Starts dks Hkh Loose dj nsrs gSaA

4 ;fn ge fdlh Movie ls Only Star dks Delete djrs gSa] rks ge ml Movie ds Producer dh Information dks Hkh Loose dj nsrs gSaA

5 Movie ds gj Star ds fy, Producer ds uke dk Duplication gksrk gSA blh rjg ls gj Producer ds fy, Movie ds Star ds uke dk Duplication gksrk gSA ;s Unnecessary Duplication Modification Anomaly dh Situation iSnk djrk gSA

bl Relation esa nks Unrelated Entities gSaA igyk Entity Movie o Stars ds chp dh Relationship dks Handle djrk gS vkSj nwljk Movie o Producer ds chp dh Relationship dks Handle djrk gSA Practically ns[ksa rks ;gh Anomaly dk eq[; dkj.k gS] gkykafd Movie, Star o Producer Entities Hkh Anomaly esa Involved gSaA fQj Hkh Theoretically tks Anomalies Create gks jgh gSa] os ,d gh Relation esa Multivalued Dependency ds dkj.k Create gks jgh gSa] ftUgsa Forth Normal Form esa Eliminate fd;k tkrk gSA Forth Normal Form dk fu;e ;s gS fd Relation Boyce-Codd Normal Form esa gks vkSj mlesa dksbZ Multi-Valued Dependency uk gksA fdlh Relation esa Multi-Valued Dependency rc Exist gksrh gS] tc fdlh Attribute A dh gj Value ds fy, fdlh nwljs Attribute B dh cgqr lkjh Values Associated gksa vkSj fdlh Attribute C dh gj Value ds fy, Attribute A dh cgqr lkjh Values Associated gksa] tcfd Attribute B o C vkil esa Independent gksaA ge ftl mnkgj.k dks Use dj jgs gSa] ml mnkgj.k esa bl izdkj dh Dependency gSA D;ksafd gj Movie Title ds fy, Stars ;k Actors dk ,d Group gS] tks fd Movie ls Associated gSa vkSj gj Movie Title ds fy, Hkh Producers dk ,d Group gS] ftuls Movie Associated gSA fQj Hkh Actors o Producers ,d nwljs ls Independent gSa] D;ksafd buds chp dksbZ Direct Connection ugha gSA bl Multivalued Dependency dks fuEukuqlkj Represent fd;k tk ldrk gS% Title ->> Star Title ->> Producer vkSj bls bl rjg i<k tkrk gS fd% “Title Multi-Determines Star and Title Multi-Determines Producer.” Functional Dependency ,d Multi-Valued Dependency dk ,d Special izdkj gS] tgka flQZ ,d eku dks Determine fd;k tkrk gS] uk fd ekuksa ds ,d Group dksA Multi-Valued Dependency dks Eliminate djus o bl Relation dks Forth Normal Form esa ykus ds fy,] gesa Relation dks Split djuk gksrk gS vkSj Relation dh Dependency ds gj fgLls dks fuEukuqlkj mlds Lo;a ds Relation esa Place djuk gksrk gS MovieStars (Title, Star) MovieProducers (Title, Producer)



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bl Design esa ge Lora= :i ls Stars o Producers dks fcuk ,d nwljs dks izHkkfor fd, gq,] Insert o Remove dj ldrs gSaA Stars o Producers dk uke Hkh gj Movie ds fy, dsoy ,d gh ckj Appear gksrk gS] ftuls os Connected gksrs gSaA fdlh Database ds Relations dks Normalize djus ij gj Entity vius Lo;a ds vyx Relation }kjk Represent gksrk gS vkSj Normalization gesa ;s lqfo/kk nsrk gS fd ge fcuk fdlh nwljs Entity dks Directly Disturb djrs gq,] fofHkUu Relations esa Data dks Insert dj ldrs gSa] Delete dj ldrs gSa] Modify dj ldrs gSaA gkykafd Normalization dh Hkh viuh dqN dfe;ka gSaA ge Relations dks blfy, Split djrs gSa] rkfd Relationships dks Primary o Foreign Keys ds Matching }kjk Represent fd;k tk ldsA ge tc Hkh DBMS ls fdlh Query }kjk ,d ls vf/kd Tables ds Data dks izkIr djuk pkgrs gSa] rc ge DBMS dks fofHkUu Relations ds chp Matching Operation dks Perform djus ds fy, ck/; djrs gSaA mnkgj.k ds fy, fdlh Normalized Database esa ge fdlh Order ds Data dks ,d Relation esa Store djrs gSa] Customer ds Data dks nwljs Relation esa Store djrs gSa vkSj Order Lines ds Data dks rhljs Relation esa Store djrs gSaA tc ge Query djrs gSa] rc ;s Query Operation bu rhuksa gh Relations ls Required Data dks izkIr djds ,d Single Table ds :i esa Prepare djrk gSA rkfd fdlh Invoice ds fy, Output Generate fd;k tk ldsA fofHkUu Tables ds Data dks Combined Form esa ,d Table ds :i esa fn[kkus ds fy, DBMS ,d fo”ks’k Process dk iz;ksx djrk gSA bl izfØ;k dks Join dgk tkrk gSA Theory ds :i esa Join Operation nks Relations ds chp Matching Values ds vk/kkj ij Records dks ;k Rows dks Search djrk gS vkSj ftruh ckj Hkh mls Match izkIr gksrk gS] og Resultant Table esa ,d u;k Record ;k Row Create dj nsrk gSA gkykafd Join Operation dks Perform djds ,d ls T;knk Relations ls Data dks Manipulate fd;k tkuk ,d vPNh izfØ;k gSA ysfdu tc Join Operations ls cgqr T;knk Records Access gksrs gSa] rc DBMS dh Performance ;kuh Data Manipulation dh Speed de gks tkrh gSA ;s tkuus ds fy, fd Join Operation ls D;k gks ldrk gS] gesa Join Operation ds Algebra dks le>uk gksxkA Relational Algebra, Operations dk ,d ,slk lewg gS] ftldk iz;ksx fdlh Relation ls Data dks Manipulate o Extract djus ds fy, fd;k tkrk gSA gj Operation nks Tables ij] ,d Single Manipulation Perform djrk gSA fdlh Query dks Complete djus ds fy, DBMS, Relational Algebra Operations dk iwjk ,d Sequence Use djrk gSA Relational Algebra ,d rjg ls Procedural gksrk gS] tcfd SQL, Relational Calculus ij vk/kkfjr gksrk gSA SQL esa gesa dsoy ;s crkuk gksrk gS fd ,d Database Relation ls gesa D;k Data pkfg,A tcfd gesa ;s crkus dh t:jr ugha gksrh gS] fd gesa Database Relation ls og Data dSls pkfg,A ,d Single SQL Retrieval Command, DBMS dks ,d ;k lHkh Relational Algebra Operations dks Perform djus ds fy, izsfjr dj ldrk gSA

Equi – Join blds lcls Common :i esa ,d Join Operation ml le; u, Records ;k Rows Create djrk gS] tc nks Source Tables ds Data vkil esa Match gksrs gSaA D;ksafd ge Rows dks



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Equal Values ds fy, [kkst jgs gSa] blfy, bl rjg dh Join dks Equi-Join ;k Natural aEqui-Join dgk tkrk gSA mnkgj.k ds fy, vxyh nks Tables dks nsf[k,% Customers Table

CustID FName LName 001 Jane Doe 002 John Doe 003 Jane Smith 004 John Smith 005 Jane Jones 006 John Jones

Orders Table

OrderID CustID OrderDate OrderTotal 001 002 10/10/99 250.65 002 002 2/21/O0 125.89 003 003 11/15/99 1567.99 004 004 11/22/99 180.92 005 004 12/15/99 565.O0 006 006 10/8/99 25.O0 007 006 11/12/99 85.O0 008 006 12/29/99 109.12

/;ku nsa fd CustID Column Customer ds Relation dk Primary Key gS vkSj ;gh CustID Column Foreign Key dh rjg Orders Table esa Hkh gSA blfy, Orders Table dk CustID mu Customers ls Belong djrk gS] ftUgksaus Order Place fd;k gSA ekuyks fd ge mu Customers ds uke tkuuk pkgrs gSa] ftUgksaus Order Place fd;k gSA ;s tkudkjh izkIr djus ds fy, gesa nks Tables dks CustID Column ds vk/kkj ij Combined Rows Create djds Join djuk gksxkA ;fn ge Database ds “kCnksa esa dgsa rks ge dg ldrs gSa fd ge CustID ds vk/kkj ij nks Tables dks Join dj jgs gSaA Join djus ij gesa izkIr gksus okyh Resultant Table fuEukuqlkj gksrh gS% Result Table

CustID FName LName OrderID OrderDate OrderTotal 002 John Doe 001 10/10/99 250.65 002 John Doe 002 2/21/00 125.89 003 Jane Smith 003 11/15/99 1597.99 004 John Smith 004 11/22/99 180,92 004 John Smith 005 12/15/99 565.00 006 John Jones 006 10/8/99 25,00



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006 John Jones 007 11/12/99 85.00 006 John Jones 008 12/29/99 109.12

Equi-Join dks ge ,d Table ij Hkh iwjh rjg ls Apply dj ldrs gSaA tc ge Equi-Join djrs gSa] rc Join ,d Source ds gj Row dks nwljh Table ds gj Row ls Compare djrk gSA First Source Table dh gj Row ds fy, ;s Second Source Table ds Columns esa Matching Data [kkstrk gS vkSj tSls gh dksbZ Matching Row fey tkrk gS] ;s Result Table esa ,d u;k Row Place dj nsrk gSA ekuyks fd ge First Source ds :i esa Customers Table dks Use dj jgs gSa vkSj Second Source ds :i esa Orders Table dks] rks Result Table fuEukuqlkj Produce gksrh gS%

1 lcls igys CustID 001 ds fy, Orders Search fd;k tkrk gSA pwafd Orders Table esa bl ID ds fy, dksbZ Matching Row ugha gS] blfy, Equi-Join Result Table esa dksbZ Row Place ugha djrk gSA

2 blds ckn CustID 002 ds fy, Orders dks Search fd;k tkrk gSA pwafd bl ID dh nks Matching Rows Orders Table esa gSa] blfy, Equi-Join Result Table esa nks Rows Place djrk gS vkSj nksuksa Rows esa nks ckj Same Customer Information dks Store djds Order dh Information dks Store djrk gSA

3 blds ckn CustID 003 ds fy, Orders dks Search fd;k tkrk gSA bl ID ls Related ,d Order gS] blfy, Equi-Join ,d vkSj u;k Row Result Table esa Place dj nsrk gSA

4 fQj CustID 004 ds fy, Orders dks Search fd;k tkrk gSA bl ID ls Related nks Matching Orders gSa] blfy, Result Table esa nks u, Rows dks Add fd;k tkrk gSA

5 fQj CustID 005 ds fy, Orders dks Search fd;k tkrk gSA bl ID ls Related dksbZ Matching Orders ugha gSa] blfy, Result Table esa dksbZ u;k Row Add ugha fd;k tkrk gSA

6 fQj CustID 006 ds fy, Orders dks Search fd;k tkrk gSA bl ID ls Related rhu Matching Orders gSa] blfy, Result Table esa rhu ubZ Rows dks Add fd;k tkrk gSA

/;ku nsa fd ;fn CustID nksuksa Tables esa Appear uk gks] rks dksbZ Hkh Row Result Table esa Place ugha gksrk gSA Join ds bl O;ogkj dks Inner Join Group esa j[kk tkrk gSA ;kuh bl rjg dh Joining dks Inner Join dgk tkrk gSA ,d Join Operation dks nks vU; Operations ftUgsa Product o Restrict Operation dgk tkrk gS] ds :i esa Hkh Implement fd;k tk ldrk gSA bl rjg ds Operations esa cgqr T;knk Data ds lkFk Manipulation gksrk gS] blfy, ;fn DBMS bl rjg ds Operations Perform djrk gS] rks Database cgqr gh /khesa dke djrk gS vkSj Query dh Performance cgqr gh de gks tkrh gSA

Restrict Operation fdlh Table ds Matching Rows dks NksMdj “ks’k Rows dks Retrieve dj ysrk gSA tcfd Product Operation nksuksa Tables ds gj Row dh Cartesian Product ds :i esa ftrus lEHko gksa] mrus Pair Create djrk gSA mnkgj.k ds fy, ;fn Customer o Orders Table ij bl Operation dks Perform fd;k tk,] rks Customer Table esa 6 Rows gSa tcfd Orders Table esa 8 Rows gS vr%



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ifj.kkeLo:i Result Table esa dqy 48 Rows Create gksaxsA bl Operation esa CustID Column nks ckj Appear gksrk gS] D;ksafd ;s Column nksuksa Tables esa Exist gSA

Database Structure and Performance Tuning Database Design djus ds vykok DBA dks ,d dke vkSj djuk gksrk gS vkSj og dke gksrk gS Database Performance dh Tuning djus dkA Database dh Performance dks Bhd rjg ls Tune uk djus ij Database ds dke djus dh Speed dkQh de gks tkrh gSA Database dh Speed dks Tune djus ds fy, gesa Database ds Design esa Hkh Modification djuk iMrk gSA yxHkx gesa”kk ,d DBMS gh User ds Commands ds vk/kkj ij Database esa Data dks Store djus ;k Database ls Data dks Retrieve djus dk dke djrk gSA ftl rjhds dk iz;ksx djds ,d DBMS Software fdlh User Request dks iwjk djus ds lHkh Data Manipulation Operations dks DBMS dk Query Optimizer gh Perform djrk gSA Query Optimizer, DBMS Software dk ,d ,slk fgLlk gksrk gS] tks fdlh Query dks Perform djus ds fy, Relational Algebra Operation ds lcls Efficient Sequence dks r; djus dk dke djrk gSA gkykafd Query Optimizer ds dke djus ds rjhds dks ,d Database Designer fdlh Hkh rjg ls Directly Handle ugha dj ldrk gS] ysfdu Database ds Design esa dqN O;oLFkk,a djds ge Database dh Performance dks dqN gn rd Increase dj ldrs gSaA

Indexing Indexing ,d ,slk rjhdk gksrk gS] tks fdlh Column ;k Composite Columns ds Data dks Access djus dk Fast rjhdk iznku djrk gSA ,d Database Application Use djus okyk User ftrus Hkh Records fdlh Table esa Add djrk tkrk gS] os lHkh Records Table ds vUr esa Random Order esa tqMrs tkrs gSaA tSls&tSls fdlh Table ds Records dh la[;k c<rh tkrh gS] oSls&oSls Table ls Sequential Search }kjk fdlh Record ds Search gksus dh Process /kheh gksrh tkrh gSA fcuk fdlh ,d vPNs rjhds dks Use fd, gq, DBMS fdlh Value dks Search djus ds fy, gesa”kk Sequential rjhds dk iz;kssx djrk gS] ftlesa DBMS fdlh Column dks Top ls Bottom dh rjQ Scan djrk gSA blfy, Table esa Records dh la[;k ftruh T;knk gksrh gS] Sequential Search dh Speed mruh gh de gksrh tkrh gSA Indexing ds Conceptual Operation Diagram dks fuEu fp= esa n”kkZ;k x;k gS%



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bl fp= esa ge Orders Table ds fofHkUu Records dk Relation ,d Index Table ds lkFk ns[k jgs gSaA ;s Index gesa”kk Sorted Form esa jgrk gS] blfy, bl ij fofHkUu izdkj ds vU; Operations Perform djds ,d Database fdlh Record dks T;knk Fastly Search dj ldrk gSA Index esa gj Record ds Keys dh ,d Ordered List gksrh gS] ftlds lkFk Order Table dk gj Record Associated jgrk gSA gkykafd Order Table ds lHkh Records Random Order esa gSa] ysfdu Index Table esa lHkh Records Sorted Order esa gksus dh otg ls Records dks Fastly Search fd;k tk ldrk gSA tc ,d ckj ge Index Create dj nsrs gSa] mlds ckn tc Hkh t:jr gksrh gS] rks DBMS dk Query Optimizer bl Index dk iz;ksx djds gh fdlh Record dks Search djrk gSA gesa bl Index dks nqckjk Access djus dh rc rd dksbZ t:jr ugha gksrh gS] tc rd fd ge bl Index dks Delete djuk ugha pkgrs gSaA tc ge fdlh Table esa dksbZ Primary Key Create djrs gSa] rks DBMS bl Primary Key ;k Composite Key ds Columns ds vk/kkj Lo;a gh ,d Index Create dj ysrk gSA tc Hkh ge fdlh Table esa dksbZ u;k Record Insert djrs gSa] ml Record ds Primary Key ds eku dks Uniqueness ds fy, DBMS }kjk Check fd;k tkrk gSA bl Uniqueness ds fy, Directly Base Table ds Primary Key dks Check djus ds ctk; DBMS ml Index dks Check djrk gS vkSj pwafd Index ,d Ordered Form esa gksrk gS] blfy, ;s Verification dkQh rsth ls gks tkrk gSA ,slk t:jh ugha gksrk gS fd DBMS gesa”kk gekjs Primary Key ds vk/kkj ij gh Index Create djsxkA okLro esa ge Lo;a Hkh gekjh Table ds fdlh Hkh Column ;k Group Of Columns ds vk/kkj ij Index Create dj ldrs gSaA ysfdu Indexing ds lkFk dqN Trade-Offs Hkh gSa] tks fuEukuqlkj gSa%

1 Indexes Database esa Extra Space ysrs gSaA pwafd vkt Disk Space T;knk egaxk ugha gS] blfy, Indexes ds lEca/k esa vkt ;s dksbZ cMh leL;k ugha gSA

2 tc ge fdlh Indexed Column ds Record esa fdlh Data dks Insert ;k Modify djrs gSa] ;k ml Record dks Delete djrs gSa] rks DBMS Base Table ds lkFk gh ml Index dks Hkh Update djrk gSA bl izfØ;k ds dkj.k Data Modification dh izfØ;k



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/kheh gks tkrh gS] fo”ks’k :i ls rc tc Table esa Records dh la[;k dkQh T;knk gksrh gSA

3 fQj Hkh Indexes Data ds Access dks fuf”pr :i ls Increase djrs gSaA lkekU;r;k Update Speed o Retrieval Speed ds chp Trade-Off gksrk gSA Indexing ds fy, ,d mfpr fu;e ;s gS fd Indexing ds fy, mu Columns dks Choose djuk pkfg,] tks SQL Query esa T;knk Use gksrs gSa vkSj Indexing lkekU;r;k Foreign Key Columns dh djuh pkfg,A ;fn fdlh Indexing dks Apply djus ij gesa yxrk gS fd Update Speed T;knk izHkkfor gks jgh gS] rks geus ftu Indexes dks Create fd;k gS] muesa ls dqN dks ;k lHkh dks t:jr ds vk/kkj ij Delete dj ldrs gSaA

Clustering Disk ij Data dks Write djuk ;k Disk ls Data dks Read djuk DBMS dk lcls Slowest dke gksrk gSA ;fn ge Data ds Disk ij Store gksus o Disk ls Data ds Retrieve gksus dh la[;k dks de dj ldsa] rks ge DBMS dh Performance dks c<k ldrs gSaA Computer esa lHkh Records Disk Page ds :i esa Store gksrs gSaA tc Hkh ge fdlh Record dks izkIr djus dh Request djrs gSa] Database ml Record ds iwjs ,d Page dks Retrieve djrk gS] ftlesa og Record gksrk gSA Page dh Size vyx&vyx Operating Systems ds vk/kkj ij cnyrh jgrh gSA Page dh Size 512 Bytes ls ysdj 4 KBytes rd gksrh gSA gesa Disk ls Hkys ,d gh Record dh t:jr D;ksa uk gks] gesa”kk Disk ls lEcaf/kr Record dk iwjk ,d Page gh Access gksrk gSA blfy, ;fn ge mu Data dks Access dj jgs gSa] tks leku Disk Page ij Stored gSa ;k tks utnhdh Page esa Stored gSa] rks ge Data Access dh Speed dks c<k ldrs gSaA bl Process dks Clustering dgrs gSa vkSj bldh lqfo/kk Oracle tSls DBMS esa miyC/k gSA Cluster dks Primary o Foreign Keys ds Matching ls cuus okys Records dks Hold djus ds fy, Design fd;k tkrk gSA Cluster dks Define djus ds fy, gesa mu Tables ds Column ;k Columns ds Group dks Specify djuk gksrk gS] ftuds vk/kkj ij DBMS Cluster Create djrk gS vkSj mu Tables dks Cluster esa Include djrk gSA fQj ftu Column ;k Composite Columns ds vk/kkj ij Clusters Create fd;k x;k gS] mu Column ;k Composite Columns ds Same Values dks Share djus okys Records dks Disk ij Physically Store fd;k tkrk gSA bu Records dks ftruk lEHko gksrk gS mruk utnhd ij Store fd;k tkrk gSA ifj.kkeLo:i fdlh Table ds fofHkUu Records dbZ Disk Pages ds :i esa fc[kjs gq, jgrs gSa] ysfdu Matching Primary Keys o Foreign Keys ds Records vDlj Same Page ij gh Store gksrs gSaA Clustering ls lkekU;r;k Join Performance dh Speed c< tkrh gSA fQj Hkh Indexes dh rjg gh Clusters Create djus ls lEcaf/kr Hkh dqN Trade-Offs gSa] tks fuEukuqlkj gSa%

1 pwafd Clustering Data ds fdlh File esa Physically Store gksus ls lEcaf/kr gksrk gS] blfy, ,d Table dks dsoy ,d Column ;k ,d Composite Column ds vk/kkj ij gh Clustered fd;k tk ldrk gSA



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2 tc iwjh Table ds Records dks Scan djus dh t:jr gksrh gS] rc Clustering dh otg ls Scanning dh Speed de gks tkrh gS] D;ksafd Clustering ds dkj.k ,d gh Table ds fofHkUu Records Disk ij fofHkUu Disk Pages esa Spread gksdj Store gksrs gSaA

3 Clustering ls Data Insertion dh Speed esa Hkh deh vkrh gSA 4 Cluster ftl Column ;k Composite Column ij vk/kkfjr gksrk gS] mu Columns

dk Modification djus ls Speed de gks tkrh gSA

Partitioning Clustering dh Reverse izfØ;k dks Partitioning dgk tkrk gSA ;s fdlh cMh Table dks dbZ NksVh Tables esa Divide dj nsrk gS] rkfd DBMS cgqr lkjs Data dks ,d lkFk Retrieve uk dj ldsA mnkgj.k ds fy, ;fn ge Music Store Application ds Database dks ysa] rks tSls&tSls Customers ds Orders dh la[;k c<rh tkrh gS] fo”ks’k :i ls Order Lines Table ds Records dh la[;k dkQh c< tkrh gSA ;fn bu nksuksa Tables esa Records dh la[;k dkQh T;knk gks tk,] rks buls fdlh Record dks Retrieve djus dh Speed dkQh de gks tk,xhA fdlh Table dk Horizontally o Vertically nks rjhdksa ls Partition fd;k tk ldrk gSA Horizontal Partitioning esa ,d Table ds fofHkUu Rows ;k Records dks Identical Structure esa nks ;k nks ls vf/kd Tables esa Split dj fn;k tkrk gSA tcfd Vertical Partitioning esa fdlh Table ds Columns dks vkil esa ,d Primary Key }kjk Linked j[krs gq, Split dj fn;k tkrk gSA nksuksa gh Partition Process ds vius dqN Qk;ns o dqN uqdlku gSaA Horizontal Partition esa ,d Table dks Records ds vk/kkj ij nks ;k nks ls vf/kd Tables esa Split fd;k tkrk gS] tcfd nksuksa gh Tables dk Structure leku j[kk tkrk gSA Music Store Database esa ge bl rduhd dks Use dj ldrs gSaA mnkgj.k ds fy, Orders o Line Items Table dks ;fn Horizontal Partitioning ds vk/kkj ij ,d ls T;knk Tables esa Divide djuk gks] rks ge bl dke dks fuEukuqlkj dj ldrs gSa% OpenOrders (OrderID, CustID, OrderDate) OpenOrderLines (OrderID, ItemID, Quantity, Shipped?) FilledOrders (OrderID, CustID, OrderDate) FilledOrdersLines (OrderID, ItemID, Quantity, Shipped?) tc Hkh OpenOrders Table ds lHkh Items dks Ship dj fn;k tkrk gS] ,d Application Program OpenOrders Table o OpenOrderLines Table ds lHkh Records dks Delete dj nsrk gS vkSj bu Records dks FilledOrders o FilledOrdersLines Table esa Fill dj nsrk gSA bl izfØ;k ds dkj.k OpenOrders o OpenOrderLines Table nksuksa esa gh Records dh la[;k de gh jgrh gS ftlls Data ds Modification o Retrieval dh Performance c< tkrh



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gSA gkykafd FilledOrders o FilledOrdersLines Table ls Data ds Retrieval dh Speed dkQh /kheh gksrh gS] ysfdu Music Store bu Tables dks cgqr de ckj Access djrk gSA bl rjhds ds lkFk rc ijs”kkuh vkrh gS tc Music Store dks Orders Table ;k OrderLines Tables ds lHkh Records dks ,d lkFk Access djus dh t:jr iMrh gSA bl rjhds dks Use djus ij tc ge fdlh Query esa bu nksuksa Tables ds Data dks Access djuk pkgrs gSa] rc gesa UNION Operator dk iz;ksx djrs gq, nks Queries dks Mix djds Data dks Access djuk iMrk gSA ;fn ge tks Application Create dj jgs gSa] mlesa nksuksa Tables dks cgqr de ckj ,d lkFk Access djus dh t:jr iMrh gS] rks ge bl rjhds dks Performance c<kus ds fy, Use dj ldrs gSaA Horizontal Partitioning ls gekjs Database dh Performance c<sxh ;k ugha] bl ckr dk irk yxkus dk dsoy ,d gh rjhdk gS] fd ge ;s tkuus dh dksf”k”k djsa fd gekjk Application bl rjg ds Data dks fdl rjg ls Access djus okyk gSA ;fn dqN Records dk ,d ,slk Group gks ftls ckj&ckj Access fd, tkus dh t:jr iMrh gks] rks ge bl rjg dh Partitioning dks vius Database ij Apply dj ldrs gSaA Vertical Partitioning esa ,d gh Table ds fofHkUu Columns dks ,d ls T;knk Tables esa Divide dj fy;k tkrk gS vkSj nksuksa gh Tables dh Primary Key dks leku j[kk tkrk gSA ,slk djus ij lHkh Tables vkil esa One To One dh Relationship ls Lined jgrh gSaA mnkgj.k ds fy, ;fn Music Store ds Database esa Titles o Prices dh Information dks dkQh T;knk ckj Use djus dh t:jr iMrh gS] rks ge Vertical Partitioning dks Table ij Apply djds mls fuEukuqlkj nks Hkkxksa esa ckaV ldrs gSa% ItemTitles (ItemID, Title, Price) ItemDetails (ItemID, Distributor, ReleaseDate, . . . ) bl Design dk Qk;nk ;s gS fd ItemTitles Table ds Records Physically dkQh Close gksrs gSaA NksVh Tables de Disk Pages esa Store gksrs gSa] blfy, bl izdkj ds Tables dh Performance dkQh vPNh gksrh gSA tc nksuksa gh Tables ds Data dh t:jr gksrh gS] rc nksuksa gh Tables dks ItemID ds vk/kkj ij Join fd;k tkrk gSA vU; Join Operation dh rjg gh bl Join Operation dh Speed Hkh de gksrh gSA



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Oracle tHe HiStOry



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Oracle – The History Oracle nqfu;ka dh cgqr gh cMh Software Companies esa ls ,d gS] ftldh LFkkiuk 1977 esa Relational Software Corporation ds uke ls gqbZ FkhA bl Company us nqfu;ka ds lcls igys Relational Database Management Software Oracle dks Develop fd;kA bls Develop djus dk igyk eq[; dkj.k Database dks ubZ Create dh xbZ SQL Language ds Compatible cuk, j[kuk Fkk vkSj nwljk eq[; dkj.k ;s Fkk fd os Database Softwares dks C Language esa Develop djuk pkgrs Fks] rkfd Database Software Cross Platform ij Run gks ldsaA bu nksuksa eq[; Requirement dks /;ku esa j[krs gq, Company us 20 lky rd bl Software dks Develop fd;k vkSj bl Software dks Oracle dk vkt dk :i izkIr gqvkA Oracle ds igys vkSj nwljs Version dks Company ds uke Relational Software Incorporated (RSI) ls gh Market esa yk;k x;k Fkk tcfd rhljs Version dks Market esa ykus ds lkFk gh Company dk uke Change djds Oracle Corporation dj fn;k x;kA gkykafd Oracle dh Stability o Reliability /khjs&/khjs Improve gqbZ tc rd fd Oracle dk ikapok Version rS;kj ugha gqvkA bl ikapos Version esa Oracle us ftl Architecture dks Use fd;k] mls vkt ge Client/Server Architecture ds uke ls tkurs gSaA bl Version esa Parallel Server Option dks Hkh Define fd;k x;k FkkA blds ckn ds NBs o lkrosa Versions esa High Performance, High Reliability o Greater Scalability izkIr djus ds Trend dks tkjh j[kk x;kA vkBosa Version ds lkFk gh Oracle ds Architecture dks fQj ls Modify fd;k x;k vkSj bls Network Computer Architecture esa Convert fd;k x;k] ftlesa Oracle Database Fundamental Part ds :i esa FkkA gkykafd Oracle 8 ds cgqr lkjs Features dks Oracle 7 esa gh Appear dj fn;k x;k Fkk] ysfdu ;s u;k Version Universal Database ds Concept dks T;knk Better rjhds ls Implement djrk FkkA Universal Database ,d ,slk Database Implementation gksrk gS] tks dsoy Relational tables dks gh ugha cfYd fdlh Hkh izdkj ds Data dks Store o Process dj ldrk gSA fofHkUu izdkj ds Data dks Manage djus ds Concept dks Oracle 8 esa Demonstrate fd;k x;k] ftlesa ge fofHkUu izdkj ds Large Objects (LOB) dks] Object Option ds lkFk Structured Objects dks rFkk fofHkUu izdkj ds Multimedia Objects tSls fd Graphical, Musical o Videos dks Mange dj ldrs gSaA vkBosa Version ds ckn ls blh Trend dks tkjh j[kk x;k gS] ftlesa T;knk Data, T;knk Users o Better Performance dks Manage fd;k tkrk jgk gSA

The Relational Database Architecture Oracle ds Structure dks ge nks Hkkxksa esa ckaV dj ns[k ldrs gSaA igyk Hkkx Oracle dk Simple :i gS tcfd nwljk Hkkx Oracle dk Advance :i gSA ;gka ge Oracle ds Simple :i dks le>us dh dksf”k”k djsaxs] ftlesa ge File-Based System, Client/Server System o Multi-User Architecture o Network Computing Architecture (NCA) ds ckjs esa tkudkjh izkIr djsaxsA fofHkUu izdkj ds Architectures ds chp ds vUrj dks le>uk blfy, t:jh gS rkfd



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ge gekjs Application o Database dh t:jr ds vk/kkj ij bu esa ls fdlh Architecture dks Choose dj ldsa ;k ,d Architecture ls nwljs Architecture ij Switch dj ldsaA

File-Based Systems Relational Database dk lcls ljy :i File-Based System gksrk gSA mnkgj.k ds fy, Microsoft Company dk Microsoft Access ,d File-Based Relational Database Management System gSA Access esa .mdb Extension ds uke dh ,d File gksrh gSA blh File esa Database ls lEcaf/kr fofHkUu izdkj ds vU; lHkh Database Elements tSls fd Tables, Queries o Forms gksrs gSaA ;s File fdlh User ds Lo;a ds Computer vFkok fdlh Network ij fLFkr gks ldrh gSSA gkykafd ge lkekU;r;k bl File ds Data dks Display djus ds fy, Access ds Form ;k Query Elements dk iz;ksx djrs gSa] blds vykok ge Visual Basic tSls fdlh Software dk iz;ksx djds Hkh MS-Access ds bl File-Based Database dks Access dj ldrs gSaA tc ge Data dks Store djus ds fy, Back-End ds :i esa fdlh File-Based System tSls fd MS-Access dk iz;ksx djrs gSa] rc gj Front-End Application tSls fd Visual Basic dks bl ckr ds fy, lko/kku jguk gksrk gS fd bl File-Based System ls Data dks fdl izdkj ls Read djuk gS ;k blesa Data dks fdl izdkj ls Write djuk gS lkFk gh ,d gh le; esa ,d ls T;knk Users leku Database ds Data dks fcuk fdlh ijs”kkuh ds Use dj ldsa] blds fy, gesa Application esa Locking Mechanism ds fy, Hkh ifjHkkf’kr djuk iMrk gSA tc ge Back-End ds :i esa Microsoft Access dks rFkk Front-End ds :i esa Visual-Basic tSls fdlh Application Developer dks Use djuk pkgrs gSa] rc Front-End ds fy, MS-Access ds Database dks Access djus ds fy, gesa JET Engine dk iz;ksx djuk iMrk gSA ;fn ge JET ds vykok fdlh vU; rjhds ls MS-Access ds Database dks Access djus dh dksf”k”k djrs gSa] rks gekjk Database Corrupt gks ldrk gSA pfy,] igys Locking Mechanism dks le>rs gSaA tc MS-Access tSlk dksbZ Database fdlh Network ij fLFkr gksrk gS vkSj mls ,d ls T;knk Users Access djrs gSa] rc fdlh le; ml Database dh fdlh ,d gh Table ds Data dks ,d ls T;knk Users Access djus ds fy, Request dj ldrs gSaA bl fLFkfr esa ;fn nksuksa gh Users ,d lkFk fdlh Table ds Data dks Access djrs gSa] rks Table ds Data ds Corrupt gksus dh lEHkkouk jgrh gSA blfy, ,d ,sls rjhds dk iz;ksx fd;k tkrk gS] ftlesa ;fn dksbZ ,d User fdlh Network ij fLFkr Database ds fdlh Element dks Access dj jgk gksrk gS] rks ml Element dks rc rd dksbZ nwljk User Access ugha dj ldrk tc rd fd igyk User ml Element dks Free uk dj nsA ;kuh ,d ,slh izfØ;k dks Use fd;k tkrk gS] ftlesa igys User ds fy, gh dksbZ Database Element Useable gksrk gS] fdlh vU; User ds fy, ogh Element ftls igyk User Use dj jgk gS] rc rd ds fy, Inaccessible gksrk gS] tc rd fd igyk User ml Element dks Free ugha dj nsrkA bl fLFkfr esa igys User ds vykok lHkh vU; Users ds fy, og Database Element Locked jgrk gSA bl izfØ;k dks Locking Mechanism dgk tkrk gSA



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File-Based Databases ds lkFk ijs”kkuh ;s gS fd ge bls c<k ugha ldrs gSaA ,d NksVs Business System ds fy, MS-Access dk Database Suitable gksrk gS] ysfdu cMs System ds fy, MS-Access tSls File-Based Database dks Use ugha fd;k tk ldrk gSA gkykafd ,d File-Based Database 100MB Data ds lkFk Successfully Deal dj ldrk gS] ysfdu tc Database esa Records dh la[;k dkQh c<us yxrh gS ;k tc ,d gh Database dks ntZuksa Users Access djus yxrs gSa] rc ,d File-Based Database dh Performance dkQh ?kV tkrh gSA mnkgj.k ds fy, ;fn ge fdlh File-Based Database ds fdlh Table ds fdlh Column esa Stored 1 yk[k Records esa ls lcls cMh Value dks izkIr djuk pkgsa] rks ;s File-Based System lHkh Records dks Network ls izkIr djsxk] fQj mUgsa Locally Process djsxk vkSj Required Value dks [kkstsxkA ,d yk[k Records dks Network ls Retrieve djus esa ,d File-Based System dks cgqr gh T;knk le; yxsxk vkSj gesa cgqr gh T;knk nsj rd Required Result ds fy, Wait djuk iMsxkA

Client/Server Architecture tc fdlh Database dks cgqr lkjs Users Use djrs gSa vkSj Database esa cgqr lkjk Data Store djuk gksrk gS] rc ge File-Based Approach dks Use ugha dj ldrs gSa] D;ksafd ml fLFkfr esa File Based System dh Performance dkQh de gks tkrh gSA ,d File-Based System ls Performance izkIr djus ds fy, gekjs ikl ,d cgqr gh T;knk Speed okyk Computer gksuk pkfg, vkSj ,d cgqr gh rst Speed dk Network gksuk pkfg,A tcfd gesa”kk ,slk lEHko ugha gksrk gSA vkt Hkh Network dh Speed cgqr T;knk rst ugha gS vkSj T;knk rst Speed okys Networks ds fy, cgqr T;knk [kpkZ djuk iMrk gSA blfy, bl leL;k dk nwljk lek/kku Client/Server Architecture esa gS vkSj ;gh og fLFkfr Hkh gS] tgka Oracle egRoiw.kZ Hkwfedk fuHkkrk gSA ,d Client/Server Architecture esa Client o Server nksuksa gksrs gSaA Client Computers T;knk Powerful ugha gksrs gSa vkSj bu ij Visual Basic tSlk dksbZ Client Application Stored gksrk gSA Server ,d T;knk Powerful Computer gksrk gS] ftl ij Database Server dks Store fd;k tkrk gS lkFk gh System ls lEcaf/kr lHkh egaxs Equipments dks bl Server ds lkFk gh Attach fd;k tkrk gSA ge gekjs Client Software dks Visual Basic esa Develop djsaxs] gkykafd Clients dks fofHkUu izdkj dh Programming Languages esa] fofHkUu Hardware Platform rFkk Operating Systems ds fy, Develop fd;k tk ldrk gSA blh rjg ls ge gekjs Server Software dks Oracle esa Develop djsaxs] ftls yxHkx lHkh izdkj ds Operating Systems o Hardware ij Place fd;k tk ldrk gSA Client/Server Architecture }kjk izkIr gksus okyh T;knkrj Advantages Server esa gh Exist gksrh gSa] tks Server dks Data ij fofHkUu izdkj dh Processing dks Apply djus dh Capabilities Provide djrh gSaA vkt ds PC brus Powerful gSa tks Data dks fofHkUu rjhdksa ls Process djds mUgsa fofHkUu izdkj dh Graphical Form esa Display dj ldrs gSaA



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Client/Server Architecture esa fdlh Database Application dks nks fgLlksa esa Develop fd;k tkrk gSA Server Part Data ij fofHkUu izdkj dh Processing djus o fofHkUu izdkj dh Information Generate djus dk dke djrk gS tcfd Client Part Server ls Generate gksus okys fofHkUu izdkj dh Information dks fofHkUu izdkj ds Format esa Display djus o Output Generate djus dk dke djrk gSA nksuksa gh Part ,d nwljs ls Lora= :i ls dke djrs gSaA

Multi-Tire Architecture Client/Server Architecture esa Hkh tc Database ds Data c<rs gSa] rc dqN ijs”kkfu;ka iSnk gksrh gSa vkSj bl Situation ds dbZ Solutions gSaA Multi-Tier Software esa ,d gh Software ds dbZ Tiers gksrs gSa vkSj gj Tier ,d Specific dke dks vPNs rjhds ls iwjk djrk gSA Tiers dks lkekU;r;k rhu Hkkxksa esa ckaVk tkrk gS%

1 igyk Client ;k GUI Tier, 2 nwljk Middle ;k Business Tier o 3 rhljk Data Tier.

Multi-Tier Architecture dks lkekU;r;k Three-Tier Architecture Hkh dgk tkrk gSA Multi-Tier Approach esa Visual Basic ,d Client dk Role Play djrk gS] tSlk fd Client/Server Architecture esa djrk gS] gkykafd Multi-Tier Architecture esa Visual Basic dks Client/Server Architecture dh rqyuk esa cgqr gh de Data Processing dk dke djuk iMrk gSA Multi-Tier Architecture esa Visual Basic dk eq[; dke Data dks fofHkUu izdkj ls Display djuk gh gksrk gSA ysfdu Visual Basic Middle Tier esa cgqr gh egRoiw.kZ Role Play djrk gS] tgka ij fofHkUu izdkj dh Processing o Business Rules dks Capture fd;k tkrk gSA Visual Basic Middle Tier esa ;s egRoiw.kZ Role blfy, Play dj ldrk gS] D;ksafd Visual Basic 6 esa ge ActiveX Components Create dj ldrs gSa] tks fd ,d Transaction-Processing Environment tSls fd Microsoft Transaction Server (MTS) ds Under esa Server ij Run gks ldrk gSA Multi-Tier Architecture esa ge fuEu lqfo/kkvksa dks izkIr djrs gSa] ftUgsa Provide djus esa ,d Client/Server Architecture Fail gks tkrk gS%

1 Create fd, x, Applications dks Deploy djuk o Update j[kuk ljy gksrk gSA ;s Architecture ml fLFkfr esa dkQh egRoiw.kZ lkfcr gksrk gS] tc ge gekjs Application dks Web ij Use djus ds fy, c<kuk pkgrs gSaA

2 bl Architecture dh otg ls tc Hkh Business ds Business Rules Change gksrs gSa] gesa dsoy Client Tier dks gh Modify djuk iMrk gSA

3 fofHkUu izdkj ds Business Rules dks Middle Tier esa Encapsulate djus ds dkj.k dksbZ Hkh vU; Application, tks fd bu Business Rules dks Access djuk pkgrk gS] og Shared Components Create djds] ,d gh Client Application ds fofHkUu Business Rules dks vU; Client Applications esa Access dj ldrk gSA

4 Business Layer bl ckr ds fy, fuf”pr djrk gS fd Data dh Security Standard fu;eksa ij gh vk/kkfjr gS blfy, Data iwjh rjg ls Stable gSaA

5 Multi-Tier Architecture ds dkj.k Application Scalable gksrk gSA



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Network Computing Architecture Oracle ds Multi-Tier Design dks gh Network Computing Architecture (NCA) Hkh dgk tkrk gSA bl Architecture esa Multi-Tier Architecture ds lHkh Features “kkfey gksrs gSaA fQj Hkh NCA esa Client dh rqyuk esa eq[; egRo Middle Tier o Back-End Tiers dk gh gksrk gSA NCA esa Multi-Tier Architecture ds rhuksa Layers ;k rhu ls vf/kd Layers gks ldrs gSaA

Clients rhuksa gh Tiers dks fuEukuqlkj rhu Categories esa Describe fd;k x;k gS] ftls ge Thin Client dg ldrs gSaA bl Architecture esa Client ,d Universal Thin Client gksrk gS] tks fuEu esa ls dksbZ Hkh gks ldrk gS%

• A Traditional Web Browser • A Java-Based Client • A Network Computer

Thin Client cukus dk eq[; Purpose ;s gSa fd dksbZ Hkh Application fdlh Hkh User rd igqap lds] fQj og User pkgs tks Operating Software Use djrk gks ;k pkgs ftl Software ds Through og bl Application dks Use djsA

Application Server Application Server ,d Special izdkj dk Software Piece gksrk gS] tks fd Middle Tier dks Efficient o Scalable cukus ds fy, Develop fd;k tkrk gSA fdlh Hkh Middle Tier Software dks Develop djus dk ,d edln ;s Hkh gksrk gS fd Server ls vkus okyh fdlh Hkh Request dks iwjk djus ds fy, ;s Middle Tier vius fdlh Hkh Code, Object ;k Component dks Server ds fy, Available djsA Application Server ,d Flexible Design gksrk gS] ftls Oracle esa Cartridges dgk tkrk gSA Cartridges os Products gksrs gSa tks Server Software ds Top ij mlh rjg ls Run gks ldrs gSa] ftl rjg ls gekjs Web Browser esa Plug-Ins Run gksrs gSaA Cartridge dk iz;ksx djds ge eq[;r% Base Application Software dks gh vius Lo;a ds Code Statements }kjk Extend djrs gSaA Cartridge dh ,d lcls cMh fo”ks’krk ;s gS fd gekjs Cartridge Code esa ;fn dksbZ Error gks rks gekjk Application Server dke djuk cUn ugha djrk gSA

Universal Data Server Data Server Layer dks Design Philosophy ds dkj.k vDlj Universal Data Server ds uke ls Hkh iqdkjk tkrk gS D;ksafd ,sls Data Server fdlh Hkh izdkj ds Data dks Handle djus esa l{ke gksrs gSaA Oracle 8 esa ge 4 GB rd dk Data Handle dj ldrs gSaA Oracle dh bl fo”ks’krk ds dkj.k ge Graphics o Video dh Information dks Oracle ds Database esa Store dj ldrs gSaA



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